The thing about trailers is that you are increasing complexity. KISS works. Like Greg Sackett, I prefer panniers for both commuting and touring. A fifty pound load is easy. If I had to bug out, I would start with more, hopefully with my 37mm reinforced tires installed.

Flat tires are the most common malfunction on a bike. If you haven't the tools and knowledge to deal with a flat, you should not consider a bicycle as an option for anything other than pleasure riding around the neighborhood.