Well I didn't look through all 4,190 albums, but you do have a very well rounded collection. I think you could use a lot of the knowledge you have to find more of what you like on your own.
Having said that ...
Get some more Zappa: "Grand Wazoo", "Roxy & Elsewhere", "One Size Fits All", "We're Only In It For the Money", "Apostrophe". (Good going on some of those George Duke MPS albums)
You don't have The Who "Live at Leeds" (a must-have)
Get U2 "Boy", their first and best album (IMHO)
McCoy Tyner "Supertrios" - easy DL from eMusic
Supertramp "The Autobiography Of Supertramp" - get rid of it. I hate that band.
Only 1 Bad Religion? Get "Stranger than Fiction", "Process of Belief"
If you like CSN&Y (you have "So Far"), get "Deja Vu" and the first CS&N album.
The Cult - "Dreamtime" and "Dreamtime Live" (eMusic)
Jefferson Airplane - "Crown of Creation", "After Bathing at Baxters"
Jefferson Starship - "Blows Against the Empire" (this is MUCH different from the later, commercial version of the band)
Return to Forever - you need the first album, "Return to Forever" (ECM)
One final question: why is the font so BIG on that Excel file?