You should do what my buddy does. He gets interested in a new rod, so he buys it for his wife, she trys it a few times, gets tired. He adds it to his collection.
If you notice your wife starting to buy you diamond earrings, you know she figured it out.
It depends on the price range you have. Sage makes their Z-Axis rods in an 8’6″ and 9′ 5 wt with a small grip designed to fit small hands, but they are pricey, though beautiful to cast. Sage also made a pink Breast Cancer rod (8’6″ 5wt in the VT2 series) last year, and although they are sold out I might know where you could find a blank to build up. I haven’t had the chance to cast the Wright and McGill but they sure are pretty.
The TFO is a good rod, but fairly stiff. I personally find it hard to control my wrist when using that rod. You might want to find her something that is a little lighter and slower. If you want to stick under $200 – check out the Echo rods. Great value for the money.
I Did some unscientific research with my wife and (12 year old) daughter. I had each one pond cast a 4,5,6 and 7wt. rod, neither one had any trouble with the handle size or style.
Of course it proves absolutely nothing but I thought you might find it interesting.