Just to be precise, I think Kyd has 99 tracks (interesting number) for AC series on official scores (all AC1, AC2, ACB and part from ACR). Majority is ambience, then fighting tracks and the smallest number is for game cinematics so that's why I think he's built the AC atmosphere (untill AC3) in a very unique, effective way (in music sense of course). So many "magical moments" for me when playing the games - AC2: main character is on a random Venetian roof, night, moon, gondola passing below and track "Sanctuary" playing... Holy shit...........
If you can, I really recommend
AC2 score in its entirety (it's the best AC score anyway imho) to get a better feel of Kyd's AC soundscape.
Now, about the Spotify links, it's unavailable for me too... However, being a commercial streaming only service I can't really say if it's desirable or not to leave Spotify links on VGMdb pages. (certainly not under 'available at' - that's reserved only for sites you can buy the album directly - if it's a digital release, available at link is where you buy it and download it, streaming only is out of question)
Secret Squirrel or Gigablah will probably give a definitive answer about it.