First of all +1 on this game, it's simple yet entertaining.
Now to the suggestions- Possibly a customizable crew, that of itself could open doors to loads of other suggestions, also a possible exp and gold per kill slope per level. I'm not sure if it happens later on in the game but all my enemies are giving me the same amount.
Mouse upgrades, I like to sit there and click the enemies while i'm waiting for my crew to regen health so maybe upgrades to make your mouse do more damage. All in all this game is great as is and I do look forward to new updates and content.
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