There should be a method of fixing the speed of pets which have been permanently slowed and which have a high monster magic resistance. Either the wand of speed monster should ignore monster MR on tame monsters, or it should be possible to break a potion of speed on the pet to remove the slowness.

The wand of speed, zapped at yourself, grants temporary very fast speed and does not grant intrinsic speed. Intrinsic speed can be gained from a non-cursed potion of speed, and a blessed potion will still grant temporary very fast speed. These would be more useful in a system where permanent very fast speed is unobtainable.