Rule 007: Wolves with Hooves
The Trample Feat currently gives any mount that successfully Overruns a target a Hoof attack. This occurs regardless of what the mount is. Instead, the line should read;
When you attempt to overrun an opponent while mounted, your target may not choose to avoid you. Your mount may make one attack with an appropriate natural weapon against any target you knock down, gaining the standard +4 bonus on attack rolls against prone targets.
Mounted Combat in general is sort of borked, but Trample stands out to me as a fairly easy fix to a glaring RAW issue.