I say several skills are widely underused, and here is my roll-into-other-skills list. Keep the ability the old skills are associated with, but have common skill points (Shadowrun used to use this, sort of).
Spot + Listen = Perception
Swim + Jump = Athletics
Hide + Move Silently = Stealth (or Prowl, or Sneak, that sounds better)
Tumble + Escape Artist = Acrobatics
Open Lock + Disable Device = Disable Device
Climb + Balance = ? uhh, Climb/Balance
Decipher Script + Decipher Language (new, and needed skill, in a world of 50,000 languages) = Decipher
I'm also a fan of lower impact magic. I wanna roll the skill checks instead of reading off a scroll of: "
I Can Do That Too, For Only 25gp"
Oh, and Concentration, so underused it isn't funny. Only see it used for casting defensively. No one ever uses it to do skills that might provoke, or to not stop drinking the potion they just got whacked for drinking. Should change it to Focus, and use it whenever you might get distracted to keep from provoking an AoO.