Sounds like you have a tuning problem, or some other engine related problem. If you have to wait that long for it to cool down, something is not quite right.
That being said, on the insulation side header wrap is nice, and it's removable. Ceramic coating is good, though doesn't usually insulate as well as header wrap. I think it's a myth that header wrap causes cracks, and I think that if your manifold is going to crack it's going to do it with or without any type of insulation material on it.
Yes, header wrap could potentially catch on fire if you have a big oil leak. If the leak is that bad, you have fire danger without any exhaust wrap also.

I've used ceramic coating on just about every engine part you can think of for our racecars, and I really like it. We usually ceramic coat our manifolds and then header wrap them for more heat rejection. We have carbon bodywork to protect though, and have to keep our inboard brakes from cooking.