I really hope some Blind Guardian comes soon. I'm a really big fan of them and would buy anything, yes ANYTHING from Blind Guardian, from Battalions of Fear to At the Edge of Time and everything in between, even most cover songs. By the way I really love that BG cover song of the song Don't Break the Circle from FtB.
Also some more Testament would be nice, I really enjoy Henchmen Ride and I'm pretty sure Electric Crown was also from RBN, maybe it was official DLC I'm not sure but yeah I would like some more Testament.
Also, here are some songs I'd like to see from Blind Guardian, if possible.
Welcome to Dying
The Script for My Requiem
Ashes to Ashes
And Then There Was Silence
Dead Sound of Misery
Ride into Obsession
I picked one from every album and if these were ever released I'd buy them instantly, same goes with any other BG music on Rock Band Network/Rock Band.
Also I'd like pretty much any song a lot from their new album, except Control the Divine and Valkyries but I'd still enjoy/buy those from the RBN.