I adored the jazzy songs on Party Queen!XD Especially the NEXT LOVE, a masterpiece!
I really liked Party Queen in general too: it's a little bit unpolished, but maybe it was meant to be so or so they say. Anyway, I think some more work would have made most of the songs perfect. But it has a great concept, amazing lyrics and it was enjoyable in every way. It's unique in its own way, on the contrary of LOVE again, which was just assembled without a real aim.
I would love for Ayu to go more experimental with jazzy and cabaret stuff, cause in my point of view she just has the right voice: her vocals in the NEXT LOVE are sublime!