You are being pretty obtuse, honestly.
So, Stark spends the first part of the film bragging about his renewable unlimited clean energy source, and then in the second act he and Banner spend an inordinate amount of time staring at monitors trying to figure out the best place that would keep the cube thing going, and, surprise, surprise, it's Stark's clean energy contraption.
Yes, as for "Legolas" I meant Hawkeye.. If you weren't so obtuse you'd get the joke/reference/whatever. And yeah, Stark lifted him up some building to get a better vantage point and to pick off aliens... but he's only in one corner of one building rooftop so from there I think his ability to see the whole city would be limted. Why not put him on Stark tower.. not only can he still pick off guys, but he could wait and see if the portal weakens at all or an opportunity presents itself to shut it down. Failing that, when BW widow suggests her stupid stunt, why not just have Cap say "no, that's a stupid plan, Hawkeye is already up there, and we'll let him look at the portal."