I wouldn't be so quick to judge the battery life quite yet. Let a few days, maybe even a weeks tops before you begin to really observe battery life. Letting the battery go through a few cycles never hurts. Not to mention, it still has the "new toy" feel to it so therefore, I'm sure your wife is more inclined to be playing with it more than she normally will be in the weeks ahead (C'mon, we all do when we get new stuff).
I agree - but I would reduce brightness level. I think once she settles in with the watch, she will get a better idea of her power usage and whether or not it is acceptable for her needs.
By the way, it is after 2pm and my watch is still at 85%. Love it.