There's lot's of space to do silly stuff with the models, sure, but it's more the Kerrigan thing I'm worried about. Updated models are likely safer than entirely new ones, too, so if there's some nice basic troops I'll likely get a bunch to compliment my older stuff, but things like adding a Supreme Commander and Superheavy unit in plastic, or some more clamshell/small box plastic heroes has the potential to be either very cool or totally shit the bed, from both a design and lore perspective.
I'm well stocked with Warriors and Hive Tyrants, and a few auxiliary units though. I'd just love new basic troops, Carnifexes and stuff like plastic Lictors - although depending on aesthetics, I'd as soon buy older metal versions of the latter two on FB sales groups.