There's an easy way to see how a 30" short scale woudl feel for you.
Detune your 34" bass from E-A-D-G to D-G-C-F.
Apply a capo at the second fret.
You now have a roughly 30" short scale bass.
The dots will be in the wrong place but try it.
Or you can play an actual short scale in a shop.
Furthermore, if you are using 'one-finger-per-fret', try instead using 'index-middle-ring/pinkie/together' like an upright bassist, at least in the lower positions.