Gosh I know what you mean about 'while you're in there'... I had to have most of my colon removed a month ago, and afterwards I was wondering, "gee, maybe I should have had him take out the appendix and gall bladder while he was in there, just in case they might cause trouble later? I mean, I don't need them anyway, right?"
Well, the thing is, the human body is wondrous marvel that we don't fully understand yet, and sometimes things (I'm thinking of ovaries in particular here, but it applies elsewhere too) have purposes we aren't even aware of. So I'd have to recommend that you not mess with anything that's not already giving you trouble, just in case.
Are you having bladder trouble? Stress incontinence in particular? If not, and if your DR hasn't suggested it, I would not recommend having your bladder worked on. Bladders are extremely sensitive and tend to cause trouble for a long time after they're handled... there are tons of threads in Post Op about this. If you don't have to tempt fate, don't, JMHO.
If you're having any doubts about whether your DR has recommended the best surgery for you, by all means seek another opinion. It will either confirm your DR's opinion (which will help you feel better about what you've decided to do) or not, in which case a third opinion would be in order. In any case, it can't hurt.
It's important that you go into this surgery feeling that you've left no stone unturned and are doing what is best for your overall health and quality of life. If you're not there yet, do whatever you have to to get there. It will help tremendously in your recovery process if you can focus on why you're going through this -- because ultimately you will have a better/longer/healthier life.
Good luck to you!