Stormstaff, for your/her requirements, I second Danbo's advice re the Inova XO LED. Just make sure it's the new version. The rugged XO's tail-switch may also be the easiest for your wife's fingers to manipulate.
The nifty Fenix L2T (better runtime than the L1T) is a possibility, but its clicky tail-switch may not hold up to the constant on-off use that many night-walkers tend to initiate -- or should be doing -- instead of thoughtless, battery-draining constant-on.
The multiple recommendation's for Surefire's bargain-priced G2 Nitrolon incan also make good sense if her walks (at dusk) are in areas of vegetation-shadowed ambient light that can wash out most mid-power LEDs. However, unless she'll habitually carry extra batteries, the G2's 1 hr. (45 min. peak) runtime becomes problematic.
I've tried over a dozen lights for our particular night-walk requirements. I want a light with a beam that (a) punches through tree-shadows and ambient light to act as my Early-Warning Radar -- alerting me as to what dangers may be lurking beyond, (b) is bright enough to warn aggressive cars/drivers who may not see us, and (c) can MAYBE temporarily stun a nasty stray dog (of the 2 OR 4 legged variety) until I can bring a better weapon to bear on the problem.
Urban parks and suburban walk-paths are magnets for Muggers/Rapists... and naive Victims. Does your wife also carry (at least) a good brand of O.C. peppergas?
While I occasionally use an Inova XO3 or SF A2 (i.e., when wet or foggy conditions dictate this), the light the works best for me 90% of the time is the great SF L5 LED. It's pricey ($150+) but its magnificently balanced beam (wide flood + good throw) touches all the bases. The L5 is built like a tank and makes an emergency impact weapon. I figure our lives are worth the extra $100 cost (plus another $25/yr for batteries) over lesser lights. I also carry a Fenix P1 (keychain) and SF E2L (pocket) as back-ups -- and I've had occasions to need 'em.
I understand family budgets, but I fail to grasp corner-cutting on crucial safety items like tires, weapons, and flashlights. For me, it's about priorities.
Good luck with your search. Your wife is lucky to have you prepare her for the realities of the Real World.
