Having only recently looked at the playlist, here are some additions I'd like to see and why. I fully understand any constraints that may exist.
Rush - it appears that the first record, Presto, Counterparts, and Test For Echo are missing. Looking at it from a prog perspective (and not a die-hard Rush fan), not having the first and Presto is OK. I think though, having Vapor Trails, Roll The Bones, and HYF w/o Counterparts and TFE is inconsistent.
I noticed the 2nd and 3rd Crack The Sky records
The debut, if available (a big if) would be great.
FM's Surveillance would be a nice addition.
I have already asked for (and are in differing stages of making it on AM) Echolyn "As The World", Manfred Mann's "Nightingales and Bombers", Discipline, and Chaos Code. In addition, the first Echolyn CD is excellent. Of course, it my also be out of print.
Wilding & Bonus' "Pleasure Signals" would be a great thing on AM. All-stars on every cut, it's a whole other level of prog/fusion. Also, the cover art is, shall I say, very magnetic.
Ronnie Montrose put out "Open Fire" in the 70's, a very prog effort by a fine guitarist.
Other artists that exist on AM in some form that I feel could be represented more are Ozric Tentacles, Frank Gambale, JL Ponty, and Steve Vai ("The Ultra Zone" being an obvious choice).
I know this is a lot in one post, but I'm doing a brain dump. Having the above selections, along with the excellent job that you guys do keeping up with current releases, really would enhance AM.