In my opinion, the problem with the current Feature-Plugin model is that it lacks the *context* of a core team-defined road map. I have long complained about the lack of a robust, publicly available, long-term road map for WordPress development.

So, without that context, the Feature-Plugin model is akin to throwing strands of undercooked spaghetti against the wall, and seeing what sticks. There's no direction, and no buy-in, either from core or from the contributor community. Thus, you end up with a bunch of Feature Plugins that wither on the vine. Too many development resources get diluted among too many Feature Plugins, with no real project-management type leadership.

I would (still) love to see WordPress development have some defined development goals and milestones. Then, direct contributor resources toward those Feature Plugins that best accomplish those goals.