Urinary and bowel complications are a big concern for me too. This is something to discuss with your potential surgeon(s), I am not a doctor, but here's my understanding of the matter.
The type of hysterectomy makes a difference in long term outcome. Check out the difference between abdominal, vaginal, laparoscopic-assisted vaginal, and total laparoscopic. Something else to keep in mind, almost all statistics on this are gonna be concerning cis women who: 1) do not have a vaginectomy 2) are not on testosterone HRT, therefore have less muscle mass than a trans man on a dose of T adequate to maintain male-typical levels 3) are not always, but often, middle age or older and would be more prone to urinary issues regardless.
To my understanding, the chance of long-term issues is minimized by getting laparoscopic hysterectomy performed by a surgeon competent in the technique (don't be shy about asking for their complication rates, how many times they've performed the operation, etc.), vaginectomy, and staying on T. With a vaginectomy the bladder is better supported than if the uterus were removed but a vagina were still present. All the better supported with T and an active lifestyle (resumed when one is well healed after surgery, consult your surgeon) to have strong pelvic floor muscles. Look into kegel exercise.
I don't know exactly what you have in mind for bottom surgery - not everybody wants a vaginectomy - but that's what my reading on the matter has told me. Odds should be in your favor, but there are no guarantees. Only you can decide if the benefit outweighs the risk.
I've put a lot of thought into it and, for me, I'd rather have the right junk and run the small risk of needing to wear some manner of adult incontinence product than put up with the current plumbing for the rest of my life. There are no guarantees of not developing these kinds of issues down the road, anyway. Getting old is rough.
