WP chooses to plug Automattic-owned ones, even when better ones exist.
This is a potential source of income for the CP project.
Provided the plugins meet a quality and security standard, yes.
I like the idea and am adding a yes vote, but, as @Ashley noted, only high quality plugins should be considered. IMHO, a very stringent standard should be applied when reviewing such plugins...a standard that applies equally to everyone. Of course, that would mean someone has to actually do the reviews... I suspect the task of reviewing plugins for "quality" is on par with writing documentation.
I agree, as long as the process, unlike the one in WordPress.org, is transparent and honest to all developers. And, of course, quality of featured plugins has to be well evaluated.
I like the idea, and I am a BIG advocate for monetization being central to CP's success and longevity.