Thanks so much for the great feedback!
We have actually planned a whole level (among others!) where you have to use the tongue ability the entire time to advance through the level. Either a vertical level where you have to use the tongue to ascend and maybe also a more horizontal level but without many platforms to land on.
Backtracking is a key element of the Metroidvania genre. Do you mean that the levels were a bit too large to backtrack in?
We will definitely work on the camera when we get more time to work on this game!