Most of the Spoiler and Persuader basses we made in the 80's were medium scale, even the 5- and 6-strings.
I would agree that balance could be an issue with the Spoiler body shape. 32 scale helps on that front, and I'd propose using lightweight tuners, a slender peghead design, and the smallest neck width that you could stand. Even then, don't expect it to balance like a Rogue or Bal K would.
First thing I would do is experiment with tuning your current Spoiler BEAD, and see if the mechanical feel of the string is to your liking - do try several different types! There are some people who can't stand the medium scale B string feel, and others that prefer it... you'll have to figure out if you have a strong opinion about the feel.
I personally love the tone of the medium scale, with any strings! It's no good if you expect it to behave like a 35+ scale length, but it has a particularly sweet tone to me.
(It's easy for me to ramble today, I'm home with a nasty sore throat, so I'm not talking!)