The AV Club asks itself which band (assuming all members are still alive) would you like to see reunited for a concert.
My top pick, which was also chosen by a couple of the AV Club people, has to be the Talking Heads. I missed them when they were together because I was too young. It's been a while, but I bet they can still bring it.
A few years ago, I might have said The Police, but then they did reunite and I made no effort at all to go see them. I'd still love to see The Pixies since I couldn't get around to seeing them when they reunited a couple of years back. I'd like to see the full Fleetwood Mac lineup too; they've been touring without Christine McVie for a few years now, which means they don't play like 1/3 of their best songs.
Other than that... all the bands I like who aren't together I've either already seen or the dead member exception rules them out (Beatles - obvs, Zeppelin, Pretenders, Miles Davis circa 58/59, original Floyd lineup, etc.).