This is indeed an area where Lilypond would need some improvement... no
matter how I tweaked the various parameters, the drum scores I got were
not very satisfying (even beginners in the class noticed problems).
There are problems with rest positioning, uneven spacing, plus some
other minor things. I had the intention of writing something documenting
the various issues--maybe we could try to write down something.
The point is that drum scores are somehow an adaptation of rhythm to a
pre-existing notation. Notes do not represent pitch, and regularity in
note disposition is much more important than aesthetic consideration, as
we're playing fast and we're playing with four parts of our body 8^).