I don't think the site need more regular shows. Most of them have proven to get a bit stale after a while. Even Unprofessional Fridays seems to need a vitamin injection soon. So I merely suggests more random content with more random people at more random times. But I guess it's harder to market irregular content, like that, to a wider audience, I dunno.
Definitely gameplay. If I don't care about the gameplay I don't care about the story. Even if it's the greatest story ever told in a video game, if it's broken up by hours upon hours of tedious chores, I don't care about it.
This goes for all works of fiction in any medium though. I wouldn't finish a book that made me watch paint dry for 2 hours in between chapters.
I think the incentive, among most honest developers, is to put out a finished product with a certain kind of polish. If you aim to trick people and make a quick cash grab you will most likely not be a long-lived developer.
That said, I'm not buying into early access (except from some bad expections in the past). Even if they have the best intentions, anything can still happen during development that result in a bad or unfinished game.