Dude, teasers and sneek peeks are the same exact thing.
This demonstrated a brief glimpse of his suit in action, the CGI, Paul Rudd's mediocre acting ability and a few other tidbits. Looking through the comments, there's people who loved the teaser and those that hated it. If it didn't whet your appetite, that's simply your taste.
Marvel did their job. Mission accomplished. Showing the public little moments from the film and going "Ah, ah, that's all we'll give you for now."
Heck, they didn't need to show the powers if they didn't want to. Of course, it would've been disappointing if they didn't, but like I already stated, teasers don't usually show much. Therefore, I wouldn't have been surprised if they decided to venture that route.
I've seen plenty of teasers where barely anything was going on, and you just had to wait for an actual full-length trailer.
Uncharted 4's first teaser was simply a shot of a map, a knife, a compass and other exploration equipment sprawled across a table. While the camera panned across the equipment, there was mysterious dialogue playing in the background. While it didn't show much, it hyped up fans for the next entry in the Uncharted franchise. It sure as hell hyped me up.
The second teaser, which was shown at E3, was an incredibly brief demonstration of the gorgeous engine Uncharted 4 was utilizing, as well as the confirmation that it was the final entry in the franchise. That, too, hyped me the [tornado fang] up.
Anyway, teasers, sneek peeks or whatever you want to call it, all come down to mere glimpses. They're quite literally, "Here's a glimpse of what we've got cooking, now be patient for an extended look at a later date."
The real meat comes from the trailers.