I would want to know about the songwriting aspect. Not "how do I write a song", but when songs were written, in which context, what they mean to the guys, all that.

At this stage, I'd have to say Jon. Richie has been in full on used cars salesman mode ever since he left/was let go from the band, and would claim to have written everything while also making it "all about the feeling, man". Jon probably would be more humble about it (think about that for a moment!) and also more cerebral.