I've gathered that we don't like having recipes with exactly one purpose. Especially when it's an intermediate step, not even an end product.
Suggestion:
We ought to remove several items: Metal Block, Plantclump, Coal Ball, Coal Chunk.
Instead of crafting these items on a table, then placing them in the Compressor, we could give the machine a crafting grid. It would either appear by default or, to keep the appearance simple, there could be an "expand view" button (or somesuch) to make the grid appear. The items would be placed in the compression grid exactly as through crafting them on a table, except that they would be immediately compressed.
Benefit:
By this method, making biofuel cells or compressing diamonds would be a bit less tedious. Additionally, we would clear out a little clutter involved in having multiple single-purpose items.