I won't go deep into animation, art, sound or the characters because all of those are OK imo, nothing outstanding but also not the worst (read grusomheds review for more details on those aspects). It would make for an allright anime show around a 4/5 or 8/10 score, wouldn't it be for one thing: the airing order is completely messed up.
For some reasons the director thought it would be a great idea to air the episodes in seemingly random order. One reason given was that they didn't wanted to end in the middle of an arc. Which doesn't make sense, since if you have 12 episodes, no matter how much you jumble them around, it will not change the amount of content you are airing.
Another reason was to shift the focus of the entire show onto one specific character. Putting aside the issue if you should change the source material, i wil raise the question: did it work to shift the focus ? My answer is a big NO. All focus is lost. The only thing you will be doing while watching is trying to guess at which point in the story we are now and which episode was before the current one and which was after the current (since often we have already seen the epsiode after the current airing).
If you're unsure of how impactful this whole issue is to your entertainment, here is how you can recreate Peach Boy Riverside: take any novel you got laying around at home which features one coherent story and has chapters. Now go read chapter 4, then chapter 10, chapter 7, chapter 3, chapter 5, chapter 2, chapter 9, chapter 1. Did you have fun ?
My recommendation to anybody interested in this show: wait until it has fully aired, google the 'correct' chronological order, and go watch it in that order.