I'd totally crop the first one right down to show the people in between the joists. If I can get a bit of time tomorrow I'll show you what I mean after work, as compositionally that's pretty good. The flat lighting kinda kills it though (maybe a bit of dodging and burning may help) and I think the angle being ftom the height we'd normally expect to see a view from here makes it look kinda ordinary. There's also somthing I can't quite put my finger on here mate, it just looks kinda formal and forced. Maybe someone else with a bit more insight can chime in.
Saying all that I really think you are very close with the first, just note quite hit it. Sorry if that sounds harsh mate, keep shooting and I'm sure you will get there!