It's very nicely done. (That's not "praise sandwich," I mean it. And I think the general style is a good fit.) Here's my quibbles:
Marshmallows over an open fire kind of suggest a holiday or weekend trip rather than "living."
The background seems much more abstract/geometric than the foreground, does that seem OK when you think about it? I don't have a strong feeling + or - but it's unusual.
If "vanlivingforum.com" was black or a dark color, instead of white with a border, it might "pop" more -- be more recognizable from a distance.
If you have one non-abstract human figure, it's going to be hard to please everybody, demographics-wise. I hesitate to suggest anything that would crowd the image more -- because simple and recognizable from a distance = important -- but if there was a way to show multiple different-looking people in a simplified or abstracted way? pop some faces into the van windows maybe? A definite vote to include some olds! ... if you're too close to the final iteration to consider something like that, never mind.
Decal in general = a nice idea!
PS is really not praise sandwich. I hate praise sandwich.