The game plays fine with the default steam proton, but the 2nd playable character and most of the enemies will be nothing but a black texture, making the game more difficult to play due to impossible to read life bars for shadowed/nontextured enemies. I can confirm that running Aces Wild with proton 5.13-6 removes the shadowing/nontexturing for the second playable character and enemies.
No other issues to report, the game plays well, without any other issues.