I prefer the idea of going shorter over longer. Easier on the tow rig, easier to get around, less expensive. But I also recognize the comfort and convenience of a longer trailer. There will be times when we may set camp for a week or two at a time... We aren't dedicated to one or the other.
Trailers get small inside in inclement weather, lots of people, bugs, cold, etc. Think through this very carefully as it is often easier to tow a longer trailer than shorter and then you will have more room inside when outside is not as pleasant. Depreciation is severe on an RV, going too small and then realizing you really wanted bigger will cost more in the long run than just getting the right size first.