A big thumbs down on compensated guns for self defense. The 19 is a pretty mild shooter as is, and shouldn't really require any compensation to make it controllable. Spend the money on a day of training with a reputable trainer on the basics of handgun manipulation, and your wife should have no problems.
Night sights are another matter - they can have a place in an SD gun, but I don't think they are absolutely necessary. I have them on all of mine, if that tells you where I stand, but I wouldn't lose too much sleep if they didn't. I don't know about any fiber optic night sights - the most common material used is tritium (fiber optic "plastic" isn't self illumintating, if I'm not mistaken).
Congrats on a sensible wife and a fine SD handgun!