I wish I could tell you that it is an easy choice and you should absolutely go with a j-pouch. But, yes there are potential complications, including not being able to construct the j-pouch.
Also, the first 3-6 months can be very trying, and many question their decision to go forward with surgery. But, in the end, the satisfaction rate is high, 80-98%, depending on the center doing the research. The main thing to remember is that there is no surgical option (j-pouch, ileostomy, or continent ileostomy) that is perfect. They all have their issues. You will never have “normal” bowel function with a j-pouch, but after you have adapted, urgency is not an issue, even though frequency may be high (4-8/day).
So, my recommendation is to not have a colectomy unless it is clinically warranted. That said, it seems you have a number of indications for colectomy: inadequate response to medications, dependency on steroids, and close family history of IBD related colon cancer. So, you probably are correct that eventually colectomy is in your future. Do you want to wait until it becomes an urgent surgery due to massive blood loss? Not the best time, but it is not possible to predict flares.
I have not noticed folks here with PSC having different function than those without it.
Oh, and for me it was totally worth it. Even though I am now on Remicade for chronic pouchitis and have IBD related arthritis. I have had UC since I was 15, j-pouch since 40, and I am 62+ now.
Good luck with your choice!
Jan 