Yo, you're very welcome! I'm so glad you loved Kaiba! I agree with you that it can be very confusing on the first watch, so I'm glad you liked it enough to dig deeper. Imo, Yuasa's works get better after revisiting them at least once. I'm actually planning on rewatching Kaiba with some friends for that reason!
Anyways, I'm happy I helped you discover a new favorite series! :)
I would list more series but they've already been recommended! Since you like Yuasa's work, I think you will like Kaiba and Mind Game. I strongly second the Serial Experiments Lain recommendation as well. :) Psycho-Pass and Steins;Gate are also good previous recs, but they're more traditionally psychological, whereas the others are psychological in more abstract and metaphorical ways.