Stanley Clarke has huge hands, plays an upright like a mandolin, and still prefers 30" basses. If guitar players of all sizes can manage the in the solo region (not to mention violinists), then we should have no problem on a 30" bass. To me scale is about sound. If I wasn't a vintage snob I'd probably be very happy with a fanned fret 30-to-34" bass.
Carles Benavent on a fretless EB-2D, with Paco de Lucía.