The end-game definitely looks intense with a huge crowd of enemies in a small space, and it would be much harder if more of them had weapons. In my experience, they were mostly unarmed, with several knife and bat users, and precious few actually dangerous people with firearms. All the enemies are quite adept at killing each other, so if you can manage to hang back for a bit, they do most of the work for you. But of course, that's the point of battle royale. :)
Maybe if you spawned several guns in the centre of the map, so that there would be more guaranteed gunslingers in the end-game?
For the movement, maybe you could add some switch between planned and auto moves? With auto moves on, you would automatically execute and end your turn whenever you would have too few energy for another action, so it would feel like going around in any other roguelike. You could then switch to planned moves in dangerous situations.