Give people the ability on the deck building screen to search for cards by energy type card type or name to prevent endless scrolling through lists.
Perhaps add some sort of on screen text (outside of scrolling text box at side of screen, perhaps something more obvious across the middle of play area) to inform players what damage has been done to their card listing and totalling all bonus received from trainer cards ect. For new players it can a bit bewildering as to why you've even been killed at times.
A display of any trainer cards used on screen as they are used for above reasons.
The ability to play against computer controlled opponents to test new decks and progress through career mode.
A downloadable version of the game so we can play offline against cpu opponents.
That is all for now thank you for all the work you have already put into this brilliant emulator I hope it remains free to play and ever growing.