Well, could be a sensible thing to do. I don't really mind the APS-C format or the crop factor, but if the money were *there* to choose either format, I think a fulll-frame outfit with just the right glass for me would be lighter or about the same weight to lug around (I still always keep film body on me,) and cost about the same. ('Being able to live happily without an FA 31' would make up for probably over a grand at this point. Right now my poor gal's substitute is a Sigma 28/1.8 which I do like, and is full frame for mah film, but is somewhat too outsized.
Since I don't actually do a lot of truly wide-angle work, it's usually sufficient to just put a basic little/cheap 24 or 28 in there for just-in-cases as I did with full-frame film. ) And the bigger viewfinder would be a big asset.
But of itself, there's nothing tragic for me about the crop format. The performance of like a K-5 or K-30 appears quite sufficient for my needs. No idea when I'll even have the money to spend.