I haven't played enough for having a good and solid opinion, but I guess that the opinión of someone with less than 30hh is somewhat usefull.
So far so good, I've encountered the game a little bit challenging compared to the originals (you basicly was stepping foward to the elite, then diying untill you leveled up a pokemon enough to kill everyone in a go, with a legendary or your starter.) The bad thing about this is the power spikes you sometimes get. Getting the soul badge was reaching level 50 with 3 pokemons that were weak to the type, and at the end had to raise a stronger one. Now everything is easy peasy xD
The seccond thing I didn't find nice was the inability of me and my friends to invite each other if we didnt talk in a chat (with that amazing spam). Maybe rooms should be made again, or adding restrictions to all, (hours of gameplay). Even creating chat rooms would be nice, a /party one at least.
Third thing: I didn't had any problem becose I like to investigate on my own and /help did gave me a lot of tips on this , but the other problem is the inability of people of understanding the gane, IV's, EV's, something that is pretty simple to understand but...
Maybe an ingame button or menu pokedex-wise with some guides would make some of the chat stop being a "rate plz, how do I get out of village x, etc etc"
The forth thing was about a "rare" spawn, been trying to capture a good chansey, I love that pokemon in my team with a masive chunk of meat, but... For 6 hours I only got hold of 1 and a horrible one xD, (I even swaped from route 13 to 14 becose I thought it was bugged or the map was wrong.) But I did understand the "why" after I asked a bit. Hope not all above average rare pokemons are that hard to find, is not like chansey is a master dueler xDD
Appart from those bits and pieces, I've been enjoying myself like a kid, hope it stays that way, the only thing preventing me from donating is actually the extra exp perk, don't want the game any easier to level up, not yet at least. Maybe a way of separating the perks or not getting them? Or a "chose the perks you want". I mean, is a donation, not paying the perks, the perks are a way to say thanks.
Sorry for my english, the mobile doesn't let me write any better neither. Glad if it's of any use ^^