The less equipment you can bring out to the gig the better, including guitars. If I do bring out a second guitar it's usually an acoustic. If your worried about tuning to drop D in the middle of a set do what I did and buy a 7th str., no more tuning issues with drop D, Eb, or drop B.
I took care of the issue of setting up a bunch of stomp boxes by replacing them with a rack mountable effects processor. I installed a power and pre-amp into my rack, so now I don't even have to bring an amp, just my rack, a speaker cab, a guitar, and an equipment bag which houses cables, strings, and accessories. It takes me 5 minutes to pack up at the end of the night. No need to keep the beautiful young ladies at the bar waiting ;)