For me, It is hard to trust a welded boat on a long mank run like bailey here in colorado. I will do roadside runs on the narrows of the poudre and boof everything, or warm up early season with the welded rock boat. I guess it shouldnt matter though, where you are on the river or what run it is. I plan on bailing my boat a time or two after it is as cracked as yours.
I think you will feel the weight of the roofing material for sure, and as soon as the bottom of the boat gets a belly it will track much worse at times. Also be ready for more cracks, and that will start to break down the roofing material.
I would like to add, this is only my experience and my opinion.
I am very stoked to hear about your cherry creek trips, isn't that what this post was really about!!