At the early stages of development I considered making splitting halve your size and spawn a slime of equal size, but the mechanic of splitting to free yourself if you get stuck in a wall stayed.
I was considering some kind of dash ability that you can use when you can't split, or at least making the slimes slightly more intelligent and follow you around. Also the slimes are intended to distract enemies somewhat (the knight in particular goes after them) but in function it doesn't seem to work that well.
and lastly, don't know if you caught it but the slime friends drop blobs if killed, which can be recollected for food.