21 days fully maxed everything.
Good start... Things I think you can improve on.
Drop the "Hold the mouse button"
Hot keys the tool/weapons
Have the mute also mute the sound and not just the music.
Add more upgrades, to make it a little longer, Also increase each ship repair by a certain amount of money each time. (10 days = 5000 9 days = 6000 etc..)
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 "Kingdom of The Wind"){kind=icon}
 "Mytheria"){kind=icon}
 "Dark Cut 3"){kind=icon}
 "Super Stacker"){kind=icon}
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