I've spent countless hours fantasizing about what my ideal superpower would be and how I would use it. This universe made into a game becomes a really exciting 2 faction dynamic that allow players to pick between Heroes and Villians and engage in conflict throughout the world zones.
I would set the game up to limit players to creating 5 characters max and powers would be assinged somewhat randomly. Players can choose from a list of default powers for their parent to have and their power would be based off of that choice.
Heroes would start at the academy, while Villians would spawn dispersed in locations around the world zones and potientially a few could spawn infiltrated in UA depending on their power.
Players would compelete objectives and fight/kill/arrest eachother for xp. The strongest hero rankings would be somewhere based off your feats and accomplishments as well as the most dangerous villian.
This style of game would offer many different playstyles and strategies. For example as a villian you could choose to remain under the radar while slowly powering up and setting up for a big score to boost your notoriety/level. A villian with more balls could just start slaughtering civilian npcs in the street, but this would instantly attract attention from Heroes looking to boost their scores. This style of gameplay would reall help immerse the player in the feel of the verse. Heroes would constantly be trying to predict where more notorious villians are going to strike so they can gain more fame. Meanwhile the villians are planning on what target to hit next and predicting who will come to intervene and how they should deal with that response.
All in all if done correctly My Hero offers a very unique style of PvP gameplay not disimiliar to GTA mixed with an MMORPG.
This would be a spectalcular world to create into a VR MMORPG. Devil Fruits may offer some balancing challenges due to their 'rarity' in the lore of OP, but Haki remains to be a perfect system for player power scaling. I would probably set the system up so as a player leveled they would gain points of some kind that could be allocated to improving the different varients of Haki.
OP also offers a wide variety of potiential playable races such as Fishman, Minks, Giants, Skypiens and many more. All of these races have unique traits and charateristics that could be converted to in game abilities/mechanics very easily.
PvP could range from 1v1 to massive PvP events like the War of the Best. Also having pirate ship battles while playing on a the pirate ship in first person using Devil Fruit powers or haki to deflect incoming cannon fire sounds exhilerating as hell.
As far as end game content that isn't focused on PvP there could be Sea King Ambushes perhaps advanced AI controlling Marine and Yanko forces. Yankos and Admirals could potientially be raid bosses. I can see shadow empowered Moria being a really fun and engaging raid fight, but I'm not sure if putting the players in the timeline with the Strawhats is the best approach for the game, by the time we reach the technological point to achieve this level of VR, hopefully OP will be finished and it may create a better atmosphere if youre the generation after Luffy seeking the One Piece. If the game was designed to be in the same timeline then it would probably be smarter if we occasionaly run into Luffy and maybe help him and the crew on their way to the One Piece. Obviously we kill them all and take it for ouselves once they find it ;).
One of the best upsides to being put into the Strawhat timeline would be that nothing would satisfy me more than beating Enel to death with a pineapple and eating it after so I could show him how a master elemental shaman would use the goru goru no mi.
Nen is an amazing power base system that can easily be integrated into an mmorpg style game and ideally would leave a lot of room for players to customize their own powers. I don't know if I would like it more if I got to choose my nen type or have it assigned randomly or through a test. The world of Hunter x Hunter would absolutely be a wonderful place to invest several years of your life in VR, if done correctly.
Players would start at the Hunter exams, after compeleting the test they would be given various options of interest to pursue based on what type of hunter they were trying to become. Based on the type of hero they choose they will get bonus xp/rewards for compeleting missions that match up with that selection. For example if a player chooses to specialize in archaelogy then they will recieve bonuses for doing things like exploring ruins and finding artifacts, but wouldn't recieve that bonus for doing a rare food collection quest.
The Phantom Troupe could roam the zones serving as a world boss style encounter and would be controlled by advanced AI. Razor would be a 10man raid within Greed Island and the Chimera invasion would be an excellent large scale PvE event were hunters are called in to stem the tide. Ideally these Chimera Ants would gain players powers upon killing them and be controlled by advanced AI. After defeating the ants players could then venture out to explore the Dark Continent!
Talking dragons that teach you badass magic that eventually lets you turn into a dragon! Fairy Tail has pages of magical classifcations and creature typings along with a built in Guild system that is the focal point of the story. This universe would be hard pressed to be anymore video game conversion friendly.
Players would be able to choose their magic type, wether or not they wanted to join or create guild. Quests and missions will become available at your guild mission table and their difficulty and rewards will increase as your guild's power and fame grows.
What missions and quests are available could be set up to change periodically ideally being drawn from a pool that has been deisgned to reduce the chance of repition as much as possible. I'm unsure as to what i would prefer in regard to having quests overlap with other guilds for example if Guild A has quest 1 would you also let Guild B get quest 1 or does that detract from the feel of Fairy Tail where guilds are in competition with eachother specifically so they can get more quests and jobs.
Most likely the most efficent way of doing things would be to have a minimum number of quests with varying degrees of difficulty based on your Guild's progression spawn per day. Then have bonus quests with higher rewards spawn for the Guilds that have cultivated more fame and renknown in the game.
End game would revolve around the Guild tourunaments and Raid encounters with bosses like Acnologia. It could be set further in the fast of Fairy Tail so dragons are more abudant to add the fantastical feel of the experience.
Hate it all you want for its popularity or out of spite for the people you know who like it. It still would be an insanely fun VRMMORPG to play.
Chakra is another ideal system for player power scaling. Kekkei Genkais and above could potientially cause balancing problems and I don't know if things like the tsukuyomi where time is distorted/altered for an individual can be transfered to a video game. I'm not really sure if it will be possible with technology to create a system that somehow adjusts the 'game speed' (for lack of a better word) to make a 10 minute play session feel like an hour.
Dual chakra types and certain Kekkei Genkais could be unlocked at certain level depending on your typing and how your building. The PvP if done correctly for this game would be insanely fun. Imagine the leading guild (probably be called a clan in the game) downing a tailed-beast and turning their top DPS into Jinchūriki and then their compitetion teams up to try and take the tailed-beast from them to slow down their Raid progression or their PvP dominance. It has the potiential to be really intricate and fun!
Hey 1v1 me lets fight all out!
First things first, you can mute or kill Asta, but probably not kill him because he's basically Anti-Mage in an all Int hero Dota2 match. This could become a caster MMO paradise free from mongoloid melees training you into the ground. Ideally no one would get the Anti-magic powers because that would be stupid, but other than that players would be able to choose what type of grimore they wanted.
Players would level from training and missions their grimore would rank up and they would be able to manipulate their magic type in more advanced ways.
Ideally players will have optimal customization over the things their magic does. There wouldn't be abilities it woud be freely manipulated by the player, but they would be limited by their level and mana/energy.
Players would be able to choose how much mana/energy to put into a attack or defense move. If a player attacks with half of their potiential output it would require an equal force to block it unless the blocking type had an advantage over the attacking type like fire and water, but if the fire spells attack power is still greater than the defending water spell with the typing advantage the water evaporates draining the fire spell of the mana/energy put into the water spell. The fire spell then continues to its target dealing the left over damage that wasn't drained to the target.
Hope that made sense!
Players would be able to choose between Soul Reapers, Quincy, and Hollows. Hybrids would cause balancing issues and break immersion. Soul reapers would start at the Seireitei and begin training and leveling up. After a certain level they would be sent to the Human world to eliminate Hollows. As a hollow players would start on Hueco Mundo as at the lowest tier of hollow and consume eachother to evolve. There would have to be some sort of time based debuff or system to prevent Hollows from spam killing eachother on a respawn point to evolve to an Arancar quickly. Quincy would start in the Human world initially train then begin taking on low level Hollow or Soul Reapers. It'd be pretty dumb and somewhat unprogrammable to have a Quincy scale to a Yhwach level. Time manipulation mechanics make my brain hurt.
End game could consisnt of raiding your way through Aizen's Hueco Mundo stronghold, the Seireitei, the Royal Guard, the Soul King and eventually fighting Yhwach, not even going to try and rationalize how you would program his abilities in a way thats not just stupidly frusterating.
All in all I'd probably play a hollow because I like the noise of their sonido more than flashstep and all of us want to be Ulquiorra at some level if we are honest with ourselves.