After thinking more about it, I think I've realized why I've been unwilling to ask for teammates or to take people up on offers - and maybe it applies to others as well: I'm assuming I don't have the skills to be successful and I'm afraid of letting other people down/dragging their jam down with me.
That's perhaps fair, but on reflection I think it makes more sense just to explain that up front while still being open to collaboration. So I'll be more clear about it now - I could certainly use someone who can generate 3D assets. However, I also intend to keep the game simple, so wouldn't expect there to be too many models. So if you're capable of making some models, even if you don't think you're good at it, hit me up and we'll see if you want to drop anything in a game. If you're a fast modeler, that should also let you work with other groups if you're so inclined, so you don't put all your eggs in my fragile, fragile basket.
Happy jamming everyone!