I agree with SueBear and I would go for surgery. Personally, I would opt for the J-pouch. There are going to be challenges no matter what age your kids are when you have surgery. But I can tell you as a mom of three children that the older they get the more involved they get in sports and other extracurricular activities and it's hard not to be there for that. Also, do you plan on having any more kids? If so, you are going to have little ones for a while.
As for the trial, that is up to you. Remicade stopped working for me after about two years and I'm on Humira now and it doesn't seem to be helping at all. I can't help but think that for a lot of people, these biologic drugs are a Band-Aid and will only work for a while. Also, IMO if someone has only had UC for a short while and they've already gone up the ladder of available UC drugs, that doesn't bode well for their colon. I know there are exceptions but I figure if 30 percent of UC patients have to eventually have their colons removed, some of these people will fall in that group.
I think the more you learn about the j-pouch, the less scary it becomes. And it sounds like almost everyone who had the surgery done would have it performed again. Good luck.