A clearer and better site scope.
Judging from what I've read about the failure of the previous Literature site - e.g. Why did Literature fail? - it seems that many of the problems there were due to either an unclear understanding of site scope, or an overabundance of questions which were on-topic and really shouldn't have been (e.g. recommendation questions). This time, let's be more proactive both about deciding on a clear scope and about shutting out questions that will be bad for the site. I plan to start several different scope-related meta threads as soon as private beta starts.
The previous incarnation of Literature was, what, 4, 5, years ago? In that time, sites such as Science Fiction and Fantasy, Movies & TV, and Anime & Manga have grown to maturity. We can now see what a successful site based on analysis of fictional works (rather than programming, mathematics, etc.) actually looks like. Many of the followers and committers of the Literature proposal are already active on those sites. I'm a mod at SFF; you're a former mod at M&TV; let's bring our experience to the table and help to make Literature great!
SE has new criteria.
As Hamlet mentions in his answer, Stack Exchange has changed its policies on closing beta sites since the previous incarnation of Literature. This time round, even if things don't go as well as I hope and the site isn't terribly active to begin with, we should be able to get the space and time we need to find our feet, fix our scope, and expand.