Rammus almost always wants to cast E and W at the same time. W has no cast time so W -> E is no problem, but E -> W will just fail if you try to W during the E cast.

This issue compounds since W doesn’t go off sometimes I get in the habit of pressing it multiple times, leading me to occasionally cancel it by mistake.

This could be remedied by allowing W to be buffered during the cast time for E. I believe other champs have similar allowances but I don’t know them off the top of my head. It’s a minor thing but would be a big QoL change for Rammus.