Giving Peter Parker spider-armor was a mistake, narratively speaking

Once he's in the armor, aren't all of his innate powers redundant, except for his Spidey sense?

This is also a problem with all the suits in Iron Man 3. Logically, if he can make that many suits he should be augmenting the Avengers with a bunch more people wearing them (perhaps with a failsafe that he can deactivate the suits if anyone goes rogue).

I was a big fan of the Iron Man comics growing up, well before they made any of the movies. But I think I had more of a sense that even making one suit was a multibillion dollar investment, such that Stark couldn't just crank out a whole bunch of them. Even if that's not how it was in the comics, they should have retconned it to be that way in the MCU.