To be honest, I don't think anymore it matters all that much. When I was younger, I carried three or four, sometimes even more guitars to a gig and used specific guitars for specific songs. Later I learned to know the benefits of just using one guitar and having a similar backup. Lately I discovered I can just use any of my guitars and I can choose depending on my mood and it will maybe have a bit of a different vibe but that's actually quite enjoyable. I have four electric guitars in standard tuning and they all work equally well, despite being pretty different beasts.
However: I've used a lot of unusual guitars like lap steels, baritones, 12-strings or kind of experimental guitars for recordings and really enjoy to widen the sonic palette, still I would not really want to incorporate those in a live show. I use a synthesizer along with my guitar, though.