Q: If I had a chord progression that was essentially a vamp between Cm9 and Bmaj7/Db, would it make sense to go to F#maj7 after that and do somthing like u did in "when I get older" where you go between F#maj7 and Abmaj7add6 ?
A: only you would know that, because only you know how you are making that sound. what's even more important is what you have for melody/words/context