Let's see here. From most to least, mine would have to be:
Twilight Sparkle Fluttershy Pinkie Pie Applejack Rarity Rainbow Dash
I can relate to Twilight a lot, and Fluttershy comes in second for the same reason. Pinkie Pie may be a bit annoying but I think it's a really honorable thing to do when you go out of your own way just to see someone smile. Applejack was my first favorite pony, but her lack of screen time made her seem a bit dull to me. Rarity, being the generous pony she is, reminds me of myself when I get that generous at times. Rainbow Dash, I'm not too fond of, but the least I can give her is that she's a good character to represent bronies to non-bronies.