No user styles? Workarounds?

(Note: I’m a recent convert to Cubase, and I’m using the GA4 Trial in Cubase 9.)

Here’s my dilemma. I want the ability to automate Complexity and Intensity that GA4 styles provide. But I also like to carefully craft drum patterns that fit closely (“lock in”) with the bass lines I compose.

I would gladly build my own styles (i.e., program my own intro, ending, main, and fill patterns and whatever variations, etc., are needed to define a style) but I gather from these threads that that is not possible:
user own styles possible ? - #8 by Steingreb - Virtual instruments - Steinberg Forums,
Why is this so freakin' hard! - Groove Agent - Steinberg Forums. (Please correct me if I’m wrong!)

What workarounds are you guys using to get the best of both worlds?

E.g., I could have a hand-crafted drum groove track in Cubase and also a GA4 track that only plays during fill sections. But then I don’t get any Complexity variation on the groove track. Here’s hoping you guys have way better ideas!

Thanks!