Thanks again every one for the great suggestions. I'm really going to look for something that can be carried or rolled a few different ways to try to account for all the different uses I would need for it.
Confession time. I had a revelation last night that winter clothes take up more room. In my defense, I've been in the south for many years and have only gone north during non-snowy periods. So I will be bringing the small suitcase next week and just dealing with it. The search for the perfect bag will continue because it will be needed, but it's no longer quite as pressing. Any help is still appreciated.