If you're looking for manga similar to Happy Smile Dream, you might like these titles.
Follows Shiro Kyoda, a young boy from Tamiya City and a student of the Bandai Elementary School. Shiro is an enthusiast of plastic model kits and "Plamo Simulation", a plastic model battle game. Shiro's dream is to become the representative of Japan in the World Simulation Tournament and be able to fight in the finals in the Battle of Hobbytopia.
Meet PET! PET (which stands for polyethylene terephthalate, a type of plastic) was a simple plastic bottle until nine-year-old Noboru Yamada recycled him. Now PET's a SUPER ROBOT programmed to protect Noboru at all costs! Whenever Noboru's in trouble, PET transforms, plugs in, and jets to the rescue! Unfortunately, PET's "help" usually does more harm than good, proving time and again that just because you call yourself "super" doesn't mean you have a clue.
The manga features Kenta Minamii and his goal to become a great player of the Pokémon Trading Card Game. It is especially notable for taking place in the real world, rather than the Pokémon world or the GB Islands.