the reason why is some enemies burst in five or more coins, so i suggested number 2 to reduce lag, as i usually get to about 110 coins and then ignore them, which means that the coins start causing lag, this would reduce it, also, one of the suggestions does go more expensive
I have a few suggestions if you ever extend the game:
1: start with less HP, but there is a HP max increasing powerup
2: make the coins just a little bigger, also five and ten coins for later game
3: make the crates able to be destroyed with bullets
4: bullet damage upgrade
5: bonus points used in a menu shop to get permanent upgrades (like a third weapons slot, unlock grenades, increase starting stats)
6: i love the reload speed upgrade, but it seems to cap out on all weapons, also it is just a little OP
7: make the shop chests get more expensive over time, but get better weapons over time
8: rocket launchers with super long reloads, but explosive projectiles
9: Make the difficulty reach a few new tiers, but only if you are on specific floors or higher (floor 10+ is nightmare if you get late enough, 14+ is Titan tier)
with these higher tiers add black (Mine layers) and silver (Stationary enemies that start spinning firing bullets)
10: more enemies!
11: damage powerups
12: Large rooms (bigger with more enemies)
13: three new room types (chest room with free chest, really rare, large shop with 3 chests, and a actual shop which shows you what you are going to get, but has higher pricing)
14: more chest types (gun type chests (gives from a category), higher and lower tier chests, mimics)
15: a whole bunch of new gun types (like a laser, a homing missile, a 8-shot, a leech gun that slowly fills hearts, a golden gun that takes coins to fire, triple and quadruple shot guns)
16: improve the speed up powerups, and get rid of the annoying side drift issue
17: rocketier enemies (T1 with regular rockets, T2 with slower, but homing rockets), ghost enemies (invisible til they get close), creeper enemies (reference to minecraft, blows you up like a regular creeper), suicidal enemies (charges in and explodes), laser enemies, and more!
18: multiplayer options (like a LAN game where you can play with friends on co-op, vs, and any other modes you want)
