Yup, find what works for you. And since you'll wind up doing some stuff by muscle memory rather than actually thinking about it, keep similar classes with a similar layout. I've got a couple accounts, and every healer except a defiler, so they're all cure-5, quick heal-6, specialty heal-7, big heal-8, emergency heal-9, and group versions of those on the secondary (ALT key) hotbar.
I've got them in the middle rather than on keys 1-5 since I've got an ergonomic keyboard; the split between 6 and 7 makes it easy to find the heals quickly when panic sets in.
