We use solid carbide compression type bits for most wood.
You have to look at chip load . Faster rpm on the spindle isn't always better. The goal to have the waste from cutting be small chips of wood not fine dust. I usually run a 4 hp spindle at 14k rpm and 320 inches per min with a 1/4" diameter 2 flute solid carbide compression bit.
You can find chip load calculators online.
Just input wood type , bit type, diameter and it will give you feed rate and rpm .