When I started playing,I was like:''Yo,this game is easy'',than I ran out of bullets and the enemies started stacking soo I only got to 96 seconds first time.
I like the hole design , good luck !
Bigger bullets can go through several enemies which makes the enemy stacking easier. I know its still a problem, but balancing takes away too much time for a jam :( I can go to about 350 seconds by managing the shield pickups to not run out of shield to be able to shoot. Spamming shots is not the right way here :)