If Avantasia went out an toured, I would prefer to see the old crew. But since that isn't happening and one-off shows =/= tour, I'd like to see some new voices brought in.
But IIRC, one of the things people have complained about the last Ayreon album was the singers. I can see Tobias' point of view. You have Marshawn Lynch, just run the damn ball for the TD.