Quality of Life
I would like to suggest some changes/features that would massively change the QoL to a positive way:
-We should be able to turn not cards (2 for one or 4 for one) to wild cards to the same rarity, maybe mythic as an exception, since there are a lots of staple rare cards, and the grind in this form is really slow, and could lead to players to stop playing the game. There are many players that don't play certain colors(for me, it's blue and white) so they should make some way to improve their favorite colors.
-You should put some paper formats in the game: In my LGS, we play pauper too, but I'm not into the format since I don't know enough cards to make a proper pauper deck on paper, and would be quite expensive to try a good amount of them out.
-Shuffling: I don't know how your code works which is responsible for the shuffling, but I think it works quite interesting. In my opinion you should try some different methods to improve shuffling. I find it really annoying when in 5 rounds straight I don't draw mana. It's a bit like the mana is managed differently from the rest of the deck.
I agree wholeheartedly, there are issues with the shuffling software, I will discuss these in my post.. also, a bargaining system for trade and wildcards..