Depending on if/how you anchor your plucking hand, a different bass can really affect that aspect of your playing as well. When I play the five, I rarely use the B string as anything other than an anchor. I might use actual notes there on one song in five, but it provides a nice anchor spot. For obvious reasons, it's a different place than where I anchor while playing a four...
I would also suspect that playing across a variety of instruments on a regular basis would make you less dependent on a particular scale or spacing. If you put a billion hours in on a shorty, though, it might be less comfortable to play a 34 or 35 inch neck. I know I wouldn't want to play a long scale fretless after the SC. I can feel the cringes from anyone out there with a great sense of pitch just thinking about it.
-bob