I switched from 4 to 5 string bass which took a bit of transition but fine now so thought I'd do the same with guitar but really struggled, it's the chords that posed a problem for me, I sold that guitar (7 baritone tuned F#) to our guitarist & built another Warmoth baritone but this time a 6 string ... no probs other than a bit if a stretch ... so I'd suggest a baritone if you're gonna tune low & hardtail bridge coz if you break a sting on a floyd rose the others will go out of tune, also bit more time consuming restringing.
Ibanez do a nice baritone (or mine that needs a loving home lol)
my 2c
Si