The odd scale length, 30.3, is the same as the 2nd fret of a standard 34 inch scale. I have a D'Addario Chromes 132 on my 5-er. So I tuned it down a full step and capo'ed it at the 2nd fret to get an idea of what it would sound and feel like.
The other EADG strings were fine. I'm thinking Chromes or Sadowsky's in 50-110 would be fine for the EADG.
But, the B string lost all definition and tone. The only B string I could imagine as working is something like a 140 or 145 D'Addario or CircleK, and then it would be so thick that it wouldn't have much overtone structure to give good tone.
And this is with a "mid" pickup. It would be especially bothersome for the neck pickup being right up against the neck and therefore really hollow and thumpy.
Now, if it had a 32 inch scale, which could be done simply by moving the bridge and tailpiece back the necessary 1.7 inches, lengthening the fretboard, and moving the pickups, it might get somewhere, because as I tuned my bass back up to pitch, I set it at a half-step flat so I could capo the 1st fret, which is 32 inches, to see what that does. It's still not perfect, but there was a noticable improvement of tone across the strings with just that half-step of extra tension. For that, a standard 45-105, or even 45-60-80-100 or 105, with a 135 or 140 B string, might actually work.
Finally, 15mm bridge saddle string spacing is just too narrow. It has to be at least 16 to be able to navigate properly.