I dunno, I chose Hector because he's practically a General, but I dunno, I prefer Lyn's storyline. She wasn't raised as a pampered royal, she lived on the plains with her mother and father, until they were killed, and she thusly left to seek revenge and stay alive. Far more interesting than "Okay, I need to protect my kingdom, Marcus, grab my sword and lets head out to the countryside and slay some Bernite's. Cheerio!" (okay, Eliwood doesn't actually sound like that, and I realize he was looking for his father, but still).
Anywho, Hector gets my vote simply for stats, Lyn for story, and Eliwood for... uh... *brainstorms something decent*... being concerned about his father?
~KaiserPhoenix