I'll add you too when I get on later.
On communications, actually that was what I was trying to do when I quit out of the band right after PubKnight was disco'ed. I figured either you could send him and invite to come back in, or maybe he wanted to send an invite so we could work on options in his band (nicely named as "Free Beer Tomorrow", btw.) I'm just as happy to join rather than run folks in my band so it's no biggie for me.
Some things that can also work are if you have two guitarits at the selection screen if someone has been doing guitar or bass for a while and would like to change around, just flick between the two choices to let the other person know you might like to change out if they are willing. Also, I'd say that some screens we should accept that occasionally someone will hold the others up on but that if they do so it's fine because it just means they needed a quick break (grab drink, hit the bathroom, deal with the crying baby) but if it's expected to be an extended break, then dropping out may be the better option and just doing the invite thing when you're done to get back into the band.
I'd aslo say that it's not a bad idea to send multiple invites just because sometimes, expecially in the middle of a set, it's easy to miss. Oh, and obviously that means the band leader will have to occasionally drop back to the invite screen to check if there are new invites (or even if someone else just happened to log into the game and we hadn't noticed them yet.)
Also another option if you'd prefer to let someone else drive and you sent an invite, just drop the band after the other person joins. Whoever that was can then send the invite in return. (That's what Ill probably do most of the time, especially since I've advanced my band, Electro Hogs, to the point where I think it may be on the Hard only parts.) Or if you want to drive but get an invite, then join, drop and then send your own invite.