Really Easy
First of al, DewclawedstormV1, the max level is not 4, you need 4 points to upgrade that ability another time. That's how the upgrading works, you need the number of points next to the upgrade to upgrade it. The max levels are 15 for Power, 10 for Range, and I didn't get to Max out the other ones, but I had 11 for Speed (which is enough to just hold Space and use the arrow keys to move at a good speed). I first levelled up Power to about 11, then I started on Speed to get to around 9. Then Maxed out Power, then got speed up to 11, then got up to level 5 in Range, then Maxed out Area. I wanted to do more, but the game ends when you get to a certain point (soon after the background is outer space) by increasing the number and speed of the strawberry clocks to an unbeatable level. My final score was 209,540. The current top score. ^_^
Easy game, after you max out power and get to 11 speed, the game is just holding space and moving up and down so it's boring for a few minutes until it ends. It's good that the author made it so you clearly lose after a certain point, instead of making the enemies harder and harder and prolonging the game which would be kinda boring to be honest. Makes it seem like you've beaten the game. Of course, an actual ending would have been nice too.
9/10