They should all be infinate payout if Steemit want to bring big name quality content creators on board.
Right now Steemit is almost like a Casino every one hoping Steem will take off and make them rich. That's not a good model for long term success or sustainability.
You think big name bloggers would bring their following to place where they can get paid only once or twice and take them away from their blog where ads pay perpetually?
Only if steem was insanely high price with payouts like they had before they might and then as soon as it dipped they'd go back to focusing on perpetual income.
If steemit wants quality exclusive content and users with followings it will have to make the payout period perpetual in my opinion otherwise it will be used as just an additional place to post content that is already elsewhere.
I think a lot of people agree with you, but the first step in this process is also making it so payouts can scale to millions of users.
Changing to a 7-day payout window (singular) helps push us towards that goal. We can push for infinite 7-day payouts after HF18, though from what I understand, there are more technical hurdles that need to be overcome before it'll work.