I think it's hard to beat that E-Z Out. Why not just get a new one? Or how about bending on the blade profile and getting a Spyderco Native? It's the least doofy-looking of the Spyderdco lockbacks.
If you'd consider an Axis lock, I like both the large Griptilian and the large McHenry and Williams. With Benchmade knives, you can adjust the tension of the pivot, or completely disassemble the knife for cleaning if you want.
My final thought is to check out Al Mar knives (
www.almarknives.com). They have some nice lockback models like the Falcon and Eagle.
Bear