OK, folks, the search is over. I took her up to Clark Guns & Personal Safety in Bossier City, LA (run by Jerry and Kay Clark Miculek), and let her handle a number of the possibilities discussed here. For those interested, here are the verdicts on the various models:
1. Glock 36: fit her hand just fine, but she's already shot mine, and found the recoil in the light gun, with the narrower grip, a bit painful for extended shooting - so, this one's out.
2. Glock 30: Too fat in the grip.
3. EAA Witness: Both she and I liked the "feel" of this gun, but it was a bit too fat in the grip for real comfort. Call this one an "also-ran". After handling it, I'm going to see if I can find one somewhere to shoot - it interests me.
4. S&W CS45 and 4513TSW: Both fit her hand fairly well, and the weight and bulk were manageable. Also count these as "also-rans".
5. HK45C: Too big and bulky.
6. Taurus PT145: No... it felt cheap and tacky, the trigger pull was nothing to write home about, and both she and I felt just turned-off by the thing. The past mechanical problems with this gun didn't help!
7. SIG P220: She really liked this gun, as did I. They had a blued one (used) for sale at $550, in very good condition. Eventually, when she chose something else, I bought the P220!
8. SIG P245: Sold! This gun fit her well, she liked the size, and it seemed the best option of all the guns she tried. Being a SIG, I have no misgivings about reliability, etc.
She went home to hubby with her new P245, and judging from a phone call he made, I think they're both happy with it. I'm willing to bet that he might want one himself (or at least a P220) for "his and hers" .45's...