I respect the discussion about how much work goes into making a Beta site into a full site, particularly from the design perspective.
From Robert Cartaino's answer:
Sending a site to the "graduation queue" and getting a design published are currently two different things. We recently hired some fantastic new designers to help clear the backlog, but there is a still about 9 sites waiting for a design, last I checked.
I'm excited about this and I really hope we get some amazing new designs.
And as stated by animuson:
Whenever there is a backlog of sites which have already been determined to have reached a point where they are ready to graduate, it is entirely up to the design team in which order they get done.
Designing sites takes a lot of time and a lot of inspiration. They not only have to write custom layouts and CSS, but they also have to think up ideas that would fit with the site nicely. Some sites are just plain harder than others.
This certainly is a lot of work and I respect people who can do it... I certainly can't... I think that the pressure would be released to a large degree if there was an intermediate step that maintained the default site design but gave the sites the "big boy" abilities, like being able to migrate questions, hold Mod elections, have community ads... and, yes, even the new rep levels for privileges.
Essentially, when a site goes into the "graduation queue", it activates the abilities and the site design can come later.
I'm not talking about this question: [Replace graduation with an incremental process] I don't want to come up with some gamified "if you reach certain bars, you get this ability!" path to graduation.
I want to release the "site design" from being the excuse for these sites not having the benefit of being a true SE site.
The most obvious downside would be that, if there's no other necessity for site design, they might not happen, or they may take even longer. I think that site designs are one of the things that make each site really unique but I also don't feel that it's the main benefit of graduation, only the most visible one.
I feel like I spoke with someone in chat on one of the Beta sites who mentioned that this might actually be what is planned for some sites but I couldn't find a question that discussed it.