So, lets make this sinple: Ettin, girallon, gray render, dire tiger, stone or hill giant would be the short list of requests. Any of them should be fine for my character. I'll be themeing them as a giant pile of wasteland under the control of the walker.
I took a look at the hivenest monster, and while it's a cool template, i'm not sure it would fit the character. Also, the dustform template interacts really badly with swarms - it's broken one way or another, depending on how it's ruled.
Combat i'll mostly be hanging back and summoning. Means I need to go off and read a guide or two there. Whee