I thought this was the old one.
You also get the Highlander flashbacks too. You get flashes of their past lives, in Ancient Egypt, in the old West, in Germany, in Thanagar, a lot of past lives where they can look different too (different bodies), but if the audience is told that this is the same guy and girl they will get it.
I really like his character, Hawkman's/Carter's. He is this guy who has lived hundreds of different lives, has been everywhere and seen everything, and is very sophisticated and cultured, but is also this angry barbarian who is trying to restrain himself. Also love the idea that he lives above a museum full of artifacts from his previous lives, and that he goes out searching for artifacts from those lives too as well as being Hawkman and fighting bad guys.
And Kendra would be the Hawkgirl I'd use, maybe call her Hawkwoman though, because her story is very interesting. She barely remembers Carter or her past lives and doesn't know if she fully trusts Carter. Plus he tells her they used to be in love for thousands of years. Its a lot for her to take and would make an interesting arc for her movie.
I don't know what the New 52 Hawkman is like, but the Johns/Robinson vesion from pre New 52 would be the one I would choose.
Oh, also you get the built in out for the actors. If the guy playing Carter wants out or the woman playing Kendra you can have them killed off and replaced with a new character. Maybe just use the idea that they did with Kendra. A descendant of Carter Hall died around the same time and his spirit went into him. Or something. But like Doctor Who you have built in outs for the actor that allow the story to keep going.
So you have the
Superman theme: alien from another planet on Earth to save it
Indiana Jones: Archaeologist and ancient artifacts and the past themes
Doctor Who: rebirth and regeneration + built in out for actors
and Highlander: flashes of past lives in different setting around the world.
I think that would help the studios see how valuable the movie could be if those themes are pointed out. Movies and shows that have already been out and worked with the audience. Themes they already know. Studios wont worry that audiences will be lost.