I might as well:
Fraternity I'd most likely join for their colors: ΑΤΩ (the azure blue and old gold just look great to me); ΒΘΠ (I really like
the sentiment that goes with the "delicate shades of pink and blue"); ΣΦΕ
Fraternity I'd most likely join for their badge: ΑΤΩ, ΚΣ, ΣΝ, ΣΦΕ (I guess I could add ΦΜΔ, since their badge looks
very similar to the badge I love the most.)
Fraternity I'd most likely join for their philanthropy: ΛΧΑ (North American Food Drive); ΣΠ (Red Cross); ΣΦΕ (American Heart Association -- great tie-in with their badge/symbol)
Fraternity I'd most likely join for their symbol: ΑΤΩ (arms and flag); ΒΘΠ (arms, flag and dragon); ΚΣ (star and crescent); ΛΧΑ (cross and crescent); ΣΦΕ (heart); ΣΧ (white cross).
ETA: If I include sororities, in terms of symbols, I'd have to go with ΑΧΩ and ΣΑΙ.
ΚΚΓ and ΠΒΦ would rank up there, too.