Vessel, the online video start-up from ex-Hulu boss Jason Kilar and CTO Richard Tom, is aiming at YouTube’s middle ground of wannabe content entrepreneurs as it launches after a 60 day beta. Vessel is designed to offer “early access to the web’s best short-form creators,” charging subscribers $2.99 per-month to get the videos, typically for an advance 72 hour window before they are available for free on other sites, including of course YouTube. Vessel has been trying to exploit some of the issues with the YouTube model for funding content as it currently is, like being difficult to make the jump from hobbyist to self-sustaining professional creator. It is not particularly targeting the occasional producer of content for whom YouTube…