I'm glad I Say Yes from Zero no Tsukaima got some attention. I think none of us realized the potential of that melody until we heard the wedding version in episode 12, which was just heartbreaking.
I didn't flip through all 7 pages here, but I'll suggest based on that top 200 list you just posted, which I assume is the summarization of this thread.
Songs from ef - a tale of memories/melodies really deserve to be in here somewhere.
Euphoric Field,
Ebullient Future,
Eternal Feather, etc...
Great songs with lots of classical influences, especially in the instrumental solos.
That aside, there's
Disillusion from Fate/Stay Night, featuring some great orchestration, the saxophone in particular.
Katayoku no Icarus from H2O ~Footprints in the Sand~. Great melody with some 'Irish-sounding' elements.
Akai Namida, the insert song of Shakugan no Shana Movie. Piano accompaniment and a wonderfully melancholy melody.
I'll come back and post more when/if I have time. I notice people tend to ignore posts if there are too many songs listed all at once. =)