First off, tremendous game. Very fun and it's such a treat to even have an AI!
My small thoughts.
Even though the Press Fire is a nice UX improvement, I don't like how it breaks the immersion, I know they are just sprites but I believe you should treat your on screen players with more care and not interchange them with letters but respect their 'life' as the player's avatar. In a similar vein when the game is complete I think it would be good to take control of the players and move them to the celebration position instead of the jump cut. I know, some tiny game feel suggestions... But maybe you can ponder on them.
Thanks for taking the time to learn all you have and climbed that hill to ascent a very tough little system to master! Great work!