A very common grinder setup to cover most tasks would be:
A flat platen
an adjustable work rest, or the ability to angle the platen
8in or 10in contact wheel
Small wheels in 1/2”, 3/4”, 1-1/2” (this all depends on you)
Ceramic belts:
60, 120
AO belts:
220, 320/400, 600
handy specialty...