Thanks for the feedback. The wall turrets are sort of designed to create "filler" bullets much like the gray tanks. About 20% of the time they do try to lead their shot to catch you off guard, but the bullet speed is a bit slow so if you're far away it's still going to be pretty inaccurate. I actually had an earlier version with more dangerous turrets. The player would not lose their shot buff (triple or fast fire) until they ran out of energy so they would have to choose between avoiding a pickup to get rid of their buff or grabbing it whenever. I felt like it was a bit unintuitive to the player so I ultimately changed it to what it is now.
As for recovering health, your suggestion just gave me the idea to maybe reward bullet grazing with slight health gain.