We did actually had a few more enemies/bosses in mind, but we wouldn't be able to implement them in time. Which is why made the current enemy scale a bit, I notice from most comments that it's still too easy so yea, that didn't help a lot :D
We can always try to make a few more enemies this week to improve the game at least a bit for after the jam^^
Will change the font for smaller resolutions, will fix that today and upload it whenever it's possible.
The cannon issue is mostly due to you being faster than the cannons itself, I will increase the speed x2/x3 and see if it feels better that way.