There are 3 cardboard boxes with more Easter eggs. We get a few references to Marvel organisations such as A.I.M., who you may remember from Iron Man 3 as an R&D agency run by Aldrich Killian, Hammer, one of Stark Industries primary rivals which made an appearance in Iron Man 2, bankrolling Whiplash and finally a box with the Stark Industries logo on it.
Correct - the hanger can only accommodate the biplane. That having been said, in order to accommodate the other aircraft too the hangar would have to be huge, with an enormous footprint, and a substantially increased parts count. As a result, I'd estimate a price up to double the current RRP which I suspect few of the target market would pay. LEGO therefore got the size of the hanger right IMHO.

The box set weighs a little over 2kg and has about 694 pieces in total, including 6 minifigures: a pilot, 3 airport workers, a male and a female passenger. The whole build would get you almost an entire airport facade with a pretty big passenger plane, an airport/control tower build, and an airport service car that tows with it a luggage, fuel and and mobile stairway.

Since around 2000, the Lego Group has been promoting "Lego Serious Play", a form of business consultancy fostering creative thinking, in which team members build metaphors of their organizational identities and experiences using Lego bricks. Participants work through imaginary scenarios using visual three-dimensional Lego constructions, imaginatively exploring possibilities in a serious form of play.[73]