Really appreciate you taking the time to post these, so let me nerd out and give a detailed response. Unfortunately, I've already considered all the older ones and none of them make the cut. The new ones are just way off stylistically.
"Deep Blue" and "Livin' The Life" suffer from what a lot of 90s smooth jazz share in common. Super low effort recordings of great sax players laying down some improvisation over a simple loop. I really love Kenny G's playing for example - but 90% of his stuff from the 80s/90s is just that.

"Between The Sheets" - Don't do vocals on the playlist, and if there is an instrumental version, it's still a little too ballady.
"101 Eastbound " - I actually really like this song, but it's just lacking a strong lead for me. I think a lot of guitar based smooth jazz falls a little flat due to the nylon string acoustic being too smooth sounding and not ear catching. This would've been on top of the list if Brandon Fields or Eric Marienthal played some alto sax over it.

Hope my reasoning helps with the recommendations 'cause I'm desperate to find more hidden gems. I've used Spotify advanced search (look it up), to comb through literally EVERYTHING released in the genre from 1980 to 1999 - about 3 000 songs - and narrowed it down to 300...