Air is very over rated imo and that's coming from someone who enjoyed Clannad and very much liked Kanon 2006 version. Anyway pretty much everything on the list above it worth watching especially Berserk, Eureka 7, FMA, Mushishi and the 2 above. You should also look into:
Full Metal Panic
http://anidb.net/perl-bin/animedb.pl?show=anime&aid=17
Lovely Complex
http://anidb.net/perl-bin/animedb.pl...anime&aid=5053
Natsume Yuujinchou
http://anidb.net/perl-bin/animedb.pl...anime&aid=5787 (Especially if you end up enjoying Mushishi)
Nodame Cantabile
http://anidb.net/perl-bin/animedb.pl...anime&aid=4691
Welcome to the NHK
http://anidb.net/perl-bin/animedb.pl...anime&aid=4121