So I'm thinking I might want to mod the ZZ when I get it. I think it'd look nice with a pair of verniers similar to what the Tallgeese line sport instead of its turtle shell backpack, but I'm not sure if I have anything like that around. I'll have to check my spare bits.
A kit you may want keep in mind would be the G Bouncer. It's thruster packs are very similar to TG's and the more narrow and sharp design would probably look good on the ZZ.
Still I wonder how much that will fill out the ZZ back, he is a pretty large guy so anything you put pack there might come across as pretty small, even more so given he is a 20 meter suit.