My problem with the ending of "Skyline"

I said I would do this after a couple of weeks It's been 2 fridays(almost, it's been two movie openings Harry Potter and Faster) so lets get to it.

My problem with skyline is simple:the human race all dies except for 1 female(I guess), really the "hero" gets stuck into an alien body in "stills" you see the hero in his new alien body put the SMACKDOWN on a few alien creatures and run away with the girl. Umm really you've just shown basically a desolate planet earth, and we don't even know if her baby is gonna make it. how is she not only gonna survive 9 months on her own (even if dude is there in his alien body to protect her) but you know RUN THE WORLD. I mean think about it:

Everybody else is gone, bodies piled along the floors of alien ships. So there will be no power, or if there is some power still on the first time it breaks down, does she know how to fix it? Is it something she can fix on her own? How is she gonna grow her own food? I mean ladies and gentleman it's not like we are this Renaissance society a bunch of well rounded men and women nope we basically have folks who grow the food, folks who fix our infrastructure, folks who push paper, and people who do various other things and RARELY do our jobs intertwine past using what someone else provides for us.

I mean I thought MAYBE an ID4 would happen we escape to some underground bunker, you figure out how and why Jarrod is how he is you regroup, come back and kick alien butt. Nope the human race is gone pimpin, and the aliens they don't waste time they blow up your skull and use the brain to stick into a new "hive mind" friendly body. Due to multiple "broken" exposures Jarrod was the only human who still had a mind of his own. Oh wait before I forget yeah the aliens do this thing wear they get the brain perfectly away from the skull and use it to power the big uglies, flying uglies, whatever ugly is in front of you right now is powered by a brain, and if you kill that brain it will just take another one, yeah absorb that.

Now if him escaping is supposed to set up a sequel okay um HIS SKULL WAS DESTROYED. it's one big alien ugly versus however large the armada was, and it's not like he can get his body back so um whats the point of showing "alien jarrod" getting away? This ain like Avatar where at the end dude changes body and now has working legs again. There is a future and a sequel on Pandora(I mean potential sequel but come on as much dough as it made it's getting a sequel probably two sequels) how will humanity come back now that they have been kicked off world, possibly is there a way for a truce to be made(you blew up a sacred tree I'd say no, but I mean you could try it). Again the end of the movie was main character opening his eyes in his new body the end. He's alive though, and there are others like him that he can start to rebuild his new home world with. But in skyline um dude if this was to keep them from trying to force you or write a sequel with or without you it's Hollywood if a movie makes money they will figure out the sequel.

So yeah bad ending, thats what I didn't like you kill the hero and don't really leave much hope for the partner/sidekick/love interest going forward. I mean what is she supposed to repopulate the planet all by her lonesome? yeah poor planning