Ok, this is what I've been working on lately, and it's NOT finished.
I started with the Iron Heroes skill set (which I think is superb), tossed Sean K Reynolds' ideas on Fewer Absolute Effects and a couple of ideas from Rich Burlew's Giants in the Playground site. Stir with my own additions of Melee Attack, Ranged Attack, and Spellcraft, and that's where it's at right now.
I need to add: Fortitude, Reflex and Will as skills (which will change how Saving Throws work, but Unearthed Arcana did much of the hard work there), and clean up the rest.
At that point, combat and spellcasting will be completely skill-based, and I'll be ready to move to levelling.