Time to close this wiki?
I think we'd make more productive use of the knowledge and proposals we've built here if it were integrated into a more active project. The strength of Wikipedia has always been around activity. If there's no activity, the value is lost. Renaming it won't make it more active, but moving it into an active project (like meta) might.
Otherwise, leave it be and protect some of the better pages.
I'm a little afraid the opposite will happen. Having our own wiki gives us individuality. If we were to merge with Meta, the distinction between our operations and theirs might become blurred, and we'd end up taking a back seat since our community is considerably smaller.
I'd like to suggest that, since there are concerns about inactivity, we promote and publicise this wiki a little more among other WMF projects. That's a potentially easier way to infuse contributors than transitioning to a new wiki, which takes some time.