than the B's are rather thick strings?I think the problem you'd have is having a 35" scale
given that the B on a StingRay 5 and Bongo 5 are practically the tightest Bs on any 34" scale basses the only thing you'd gain on a 35" scale 6 is a C that's a little too tight and possibly choked. A 34" scale C is gonna be a sweet less guitar-like sounding C from what I'd expect.
My 6 (not a Bongo 6...yet) is a 35" scale and feels great but the C is definitely a little on the tight side. So I do bleeeb that a 34" scale 6'er is gonna rock.