Luna... She's the only one except Ron and Hermione, Harry felt comfortable talk to. After Sirius' death?
I still feel that Ginny not even understand Harry completely...
Even now, I support Harmony coz Hermione is the logical girl for Harry.JKR might try to show Harry-Ginny's love as true and meaningful, but I personally think it is nothing more than immature teenage flirtation and not something deep as she tries to make us feel (at least to me)
I find Harmony to be a much more sensible combination than Harriny - So I'm a Harmony fan all the way.My second choice would be Luna.
He'd have been good with Luna. They really got along, and I feel they'd have done well together. Their personalities mesh really nicely, and I believe that is a key to a successful relationship. :)