I think the first thing that would need to be set is the type of music and should you build your super group around that. I mean that I would choose Steve Harris from Iron Maiden as my bass player, but you could not really put him along side BB King. Or could you, that is the question.
After a week or so of thinking here is what I've come up with so far:
Geoff Tate - Queensryche
Steve Harris - Iron Maiden
Unknown at this time- possible choices might be: George Lynch (Dokken,Lynch Mob),Rik Emmett(Triumph), Brad Gillis(Night Ranger)Steven Gaines(Lynyrd Skynyrd)
Ditto-Kenny Wayne Shepherd,Buck Dharma,
Rudolf Schenker - Scorpions
Neil Peart-Rush, John Bonham-Led Zeppelin
As this is a list based on one's own taste in music. I do understand that there are some serious omissions in this list such as Jimi, Eric and such on Guitar. I believe that when you put together your dream group, you have a sound in mind that you are going to create and as such, putting together muscians that will actualy be able to create the sound that you want. I just don't see putting Muddy Waters with Eddie Van Halen together.