GSD, so far, has been put forth a lot like star wars. I don't know if you guys have already heard of this before, but there's a lot of characters that are very similar between the two space operas. i may be reaching for some of these, but here they are..
first, we'll start off with an obvious one:
shinn is anakin skywalker
-both use angst to fight. a bad past shapes their present, and thus at times considered emo. through their anger, they have power, and they wield it in battle.
dullindal is senator/supreme chancellor palpatine
dullindual is manipulating something behind the scenes and you know it. he bails out shinn, gives captain gladys and athrun FAITH. also, with the EAF ranking under his control, he has a shot of starting a military dictatorship. no different from the actions that palpatine took.
kira is luke skywalker
both stories are the same. luke, a backwater civilian of Tatooine, one of the last Jedi's, makes it big. Kira, an inhabitant of Heliopolis gets inside a Gundam (one of the few coordinators blessed with seed mode) and makes it big. in their debut stories, they both come off as whiny protagonists but at the end, they have matured. luke matured from ESB to ROTJ just like how Kira matured from GSeed to GSD.
the final one, imo is really reaching, but here it is..
Neo is Darth Vader
mwu dies and Neo is born! henchmen of a mysterious person (the weird EAF director). what else is there to say? although not exactly the same as vader (not having a son or anything) mwu dies to protect the one he loves. he is 'freed' from his bonds later in GSD.