Here are some issues I've faced with.
1) A lot of bugs in the browser version for the phones A) every time I try to change the flow in the dungeons, it throws me away, it makes it complicated to finish some tasks and annoying b) sometimes, when I win the game, it shows we an error with the internet connection, but all others websites and apps work well. Needless to say: I lose my time and scores in the tower c) after you updated the game by making it possible to "rotate the phone to experience bla bla bla" it glitches a lot and sometimes doesn't even reacts to any commands (literally impossible to scroll up or down.
2) Gold issues. If you make such a big price for leveling up girls on a high level, at least give us a proper amount of gold in the chest both: for the quests and in the Tower. Can you imagine how much should I play if I want to level up a Mythic girl for level 11? Right, 7800 gold. Do you know how much profit do I gain for that> Right, +12 damage. It's ridiculous.
3) A lot of quests are strange and have no logic. For example, *kill 45 event monsters*. In order to finish it, I have to enter the game every 24 minutes for a couple of days. Meanwhile, "Open 4 chest in the shop" - I have to enter the game once every 4 hours. Quite a difference. Just to make it less annoying, at least give us 3 event quests at the same time, so it will give us more pleasure to play.
4) Content. Please, dd more content. You need money, ok, we got it. We can get the Mythic event girls only if pay money, ok, let it be so. But what else should we do in the game on the high level, since the top 25 in the Tower 1 is unapproachable if you have a personal life? Give us something more to play: Arena 3x3 ( at least it gives the sense to have such a huge collection, so we finally could use a couple of sets instead of only one). Make some special bosses ( for example 5 different bosses, every each of is immune to the specific element ( light, forest and etc) it will give us a need to level up other cards, not only ones, we are maining.
Your game is cool. I really like the design. But management has a lot of room for improvement.