So sorry that your mother, and you, are facing this. She is lucky to have you by her side. I will try to answer a few of your questions, although I have not had a cystectomy, I do know a lot of people who have.
First, while there are three general diversion types, they are not all suitable to everyone. The Neobladder, when it works, can be wonderful. When it doesn't, the patient can be left either incontinent, or hypercontinent, requiring routine cathetering. It is also often not as successful in women as in men, and the surgery for it is the most complicated.
The Indiana pouch does require a catheter to empty the reservoir through a stoma in the abdomen. Both the Neobladder and the Indiana pouch require a surgeon who does a lot of these specific diversions.
The ileal conduit is the simplest surgically. Afterward the patient wears a "bag" (similar to that used with a colostomy, to collect the urine.
I know that you have read up on these, but if you haven't seen this web site it is worth checking out
my.clevelandclinic.org/health/articles/urinary-reconstruction-and-diversion.
All of these surgeries are major surgery and require a relatively long recovery time. Whether or not the patient needs to spend time in a rehab nursing facility depends first, on how able the patient is to take care of themselves, and second, on what kind of support and help she has at home. At the minimum your mother would need someone with her for quite some time who is competent to help her deal with the new reality.
There is, of course, discomfort following the surgery until the body is healed. But there should not be any chronic pain after the recovery period. Most patients adapt well and lead normal lives. We have members who ski, scuba dive, and drive race cars!
Hope this helps a bit.
Sara Anne