To an IFR you can order to climb, descend, turn... anything. With VFR you canīt. Thatīs a big difference.
Right !... and not.
Back in years, I had this discussion with a colleague who crossed the TMA I controlled.
When she landed, she told me that my method to "impose" altitude to VFRs wasn't legal.
I answered that altitude wasn't imposed : transit was approved at a precise altitude, any other altitude being refused.
I don't remember having refused any transit. I guess most of the time, people prefered changing by 500 or 1000' than wait outside.
Suggesting a trajectory (heading) to a VFR is not illegal either, as long as he agrees. We just have to get him back to a point from which he can start his navigation again. This is more work (but also more fun) than just say : "Stay outside".