100% agree with those changes, like I said for me the enemies were really fast, I couldn't cross the other side of the map without being bombarded by enemies, and the rate of fire is slow so I couldn't get them in time. This would totally fix it though, and I agree with the ammo pickup, I found myself waiting for ammo to spawn. But! You can keep the speed boost random like how it is now, it would be fair to change the way ammo spawn works.
Followed you to see the future updates for the game, when there's a steam release I'll give you a wishlist to boost the algorithm for you on release day :D