Everyone's doing the suggestion thing now and trying to work on selections? I'll update my list for the hell of it:
One Piece (I have a feeling Toonami could make this one blow up DBZ style, especially with Funi's dub washing the bad taste of the 4kids dub out of everyone's mouths)
Bleach
Naruto
Hunter X Hunter
Soul Eater (Can't believe I forgot this one, the first episode alone is something I could see a lot of people enjoying -- maybe it could lead to a "Brotherhood" second take series with the new exposure?)
Fullmetal Alchemist: Brotherhood
Fairy Tail (eh not all that, but Toonami did put on Rave for a time...)
Katanagatari/Sword Story
Casshern Sins
Tengen Toppa Gurren Lagaan
Big O (Maybe a Part III?)
Sword of The Stranger (movie but hey...)
The Last Exile
Michiko E Hatchin
Medaka Box
New Lupin The 3rd
Kids on The Slope
Beelzebub (Good for that gag series pick)
Thundercats
Young Justice
Batman:TAS/Beyond
Green Lantern
Someone here suggested Panty, Stocking & Garterbelt and I'm in tears imagining how that would work, more risque Toonami or not. :lol
Whatever the case though, it's absolutely mandatory that the OG Toonami shows have a rotation. I'm talking DBZ, Rurouni Kenshin, YuYu Hakusho, Cyborg 009, Ronin Warriors, Gundam Wing/G Gundam, Outlaw Star, Tenchi Muyo, hell even Sailor Moon if they got ballsy enough to get that license back. From the shows that still see airings on AS, FLCL, Big O, Trigun, Samurai Champloo & Bebop could be strong "oldies but goodies" picks. They should also definitely try to get some of those old school western productions in for a good mix like the Batman/Superman TAS, Reboot, Teen Titans, Justice League and the like. You wouldn't believe how effective the lineup shown on Saturday/Sunday morning was for a lot of older animation heads. Building off that while introducing more modern content that fits with the overall Toonami style is the way to go.