I prefer diesels also, but that's just my preferences. As for range, look at the size of the fuel tank also. Some come with awful small tanks.
Yes trailers can be pulled in snow, you just need enough truck weight to control the trailer. The truck may pull it, but will it stop it? Think of all the trucks pulling large enclosed four place snow machine trailers. The ones I see having problems are the lightweight 1/2 ton shortbeds with crappy all season radials, with no weight in the bed, that can't control the trailer especially in the corners.
No I wouldn't put chains on the trailer unless you absolutely had to travel on glare ice. But you should just stop wherever you're at and wait it out.
Bill