This is fun for sure and has a lot of potential but definitely can veer into a little frustrating at the moment. TheSoulSelector's feedback on an incoming enemy would be great as a way to avoid those "I was killed on the edge of the screen" occurrences.
Otherwise I think slowing down the speed and introducing that as a way to introduce difficulty incrementally would be great. As well as adding obstacles to the level for some variety/added strategy in traversing around enemies.
I also liked the little delay when reviving another life, the angles that would come up from resulting fire added a nice effect. Although it was a bummer when you'd struggle to maneuver reviving someone and they'd get taken out immediately. I think slowing down the movement would resolve that though. Good work!