I'm afraid I've never worked with the suite lists stuff. Just exported my suite and that's that. I'm not quite sure why you'd need all that junk though -- after all, nothing stops you from requesting different versions of the same suite, I do that with Illustrator in our core product.
Unless you're looking to enumerate the available suites, in which case I'm not going to be much help :P
As for PIPropertyList, are you talking about the stuff in SPProps.h? Because there's almost nothing in the SuitePea headers having to do with the PIPL that actually works in Illustrator. I've messed around with a bunch of the callers & selectors that are *supposed* to come in, and they don't. I talked to a couple of the AI developers a couple of years ago and they told me the AI PIPL stuff is basically a greatly stripped down version of the stuff found in Photoshop's SDK. -- basically, there are a lot of functions that do nothing.
From looking at AI's shipped-with plugins, you can see that there are a few PIPL options that seem to be present -- most notable the EXPT directive that *seems* to publish something indicating what suites are available. I say 'seems' because I've never had much luck making a PIPL that actually worked with that directive -- and it doesn't help that the only tools for working with a PIPL in plain text ship with Photoshop, not AI. It's probably telling that the developers told me that a number of their shipped-with plugins just use the PIPL that comes with the SDK!