Is Duik supposed to be this clunky?

I've got some client work animating their characters for some stuff and I'm pretty sure this is their first go at rigging in AE and while it's new to me, too, I have spent two days now just making the scene possible to animate, mostly spent just waiting. The imported rig has over 300 layers, the shape layers are each the size of the whole illustrator document the assets were made in (so there are massive invisible document frames flying around), and each minor change takes like twenty plus seconds to render clearly enough to see if I'm not breaking something, even at Quarter resolution preview. The main comp is 1920x1080 but the rig's comp size is like 3000x4000, and I can't do any animation in the main scene, and oh, boy, it chugs

So I have some questions:

• When you convert an AI file to shapes from a vector layer, does it always make the result as large as the original AI file? I've found I've had to go into each one and delete all the excess layers/groups it makes for new assets. Is this avoidable?
• Is it possible to animate outside of the rig comp? I've imported the scene BG into it to get an idea of where things will be in the actual animation scene, but I think that's giving AE even more to render
• How performant is a normal, but well-made rig, even with lots of features that need plugins like SFCaddy? Is this just par for the course with Duik?

I'm mostly just venting. I still have a second character to work through before I can really get to animating, but I'm sure even then it's going to be an absolute chore given the energy the client is needing for the production..