Geldor ranks high no matter what. He was high on our list and he was #1 on the German list. He's definitely up there.
He's a cool villain! I'd like to see him as a figure as well as Illumina.
Even though I like the thought of Evilseed being a plant guy from the start,
maybe in MOTUC Geldor became Evilseed after the tree absorbed him. It would also be another inroad to Evilseed.
...and then Illumina had Sleetah drag Evilseed up into the arctic and left him there, until he was found by some followers who thawed him out. It's all one perfect circle!