Ravenous Bugblatter Beast of Traal
It has an advantage (melee weapon PCs doa bit more damage) and an offsetting detriment (melee attack foes - which is a very common category - do more damage to PCs). It's likely a net penalty to the PCs because of how common foes with melee attacks are, and at best is even.I support degrees of success and failure, but I don't really want anything that straight increases PC power.
EDIT: Please also remember the context of the thread - it's about always hitting. If there are issues with that in general, air them in a more inclusive way then targetting at one proposal.