I realize of course they will never add new skill / perk trees for these, but I could definitely see three additional skills having been integrated into the skill system, balanced among the wizard, thief and warrior constellations respectively: Staves, Hand to Hand, and Polearms & Flails.
Polearms & Flails could include whips, etc., plus weapons that require different combat styles than those currently in one- and two-handed (e.g. spears, naginata, bo sticks) and have perks similar to those in other melee skills
Staves perks could unlock enchanting options with found, unenchanted staves (which are in the CK, I believe, or better yet add new staves via DLC that correspond with existing smithing materials / styles), along with opening up melee uses for staves (similar to staves in Morrowind)
Hand-to-Hand... I dunno, some crazy Bruce Lee [censored], I expect.

I never RP a monk, but I'm sure others would have some fantastic ideas. And I know Hand-to-Hand is beloved among a lot of TES players. So, why not have the option?