Pluses:
1.Good aesthetics
2.You avoid overloading players with information about game mechanics.
3.Guild missions are interesting.
Minuses:
1.Need to reopen all missions and make all progress form scratch when you make new version of game (yes, it's possible to copypaste your login, but you don't warn people that you make an update). It would be helpful if you made "cheat mode" that unlocks all missions (and allowed to play guild missions in arbitrary order for sake of playtesting), all stars and infinite gold. It would make playtesting easier. And it would be possible to satisfy curiosity about new version of your game without hurdle
2.You don't publish changelog for all new versions here.
3.A player needs to constantly click wave icon in order to get wave early. It would be cool if there was option for always calling wave early automatically (for players who want additional challenge)