Kinda depends on how I rank, when I think about best albums in terms of which ones are most packed with my favorite songs, it would probably go
Ghost Reveries (The mellow songs don't get all that much attention but the 5 heavy songs are all epic for me)
Blackwater Park
Still Life
In terms of the album as a whole, where I'd probably judge by which ones I love playing start to finish...
Still Life
Watershed (I think it flows pretty well, especially between Coil and Heir Apparent)
My Arms, Your Hearse