I'm surprised it's coming out so soon, honestly. Good on Warner Bros. that they are putting these movies out with more frequency. I think they need to really consolidate their efforts and form an in-house team of directors, writers and artists. This way, they can put out 4 DTVs a year (1 per quarter) with a rotating group of personnel. For example, I think the best formula for DTVs would be:
1. A Batman or Superman movie every year, since they are the highest sellers and bring the most attention to the line.
2. A team-up movie (Justice League for example) which is always appealing.
3. A solo movie for a character other than Batman or Superman.
4. Anthologies or something a little more experimental, possibly featuring more obscure characters. Possibly double features that include 1 popular character and another less-known one.
The best way to consistently put these movies out would be to have a rotating set of 4 or 5 directors. People like Lauren Montgomery (Superman: Doomsday, Wonder Woman, Green Lantern: First Flight), Joaquim Dos Santos (Justice League Unlimited, Avatar: The Last Airbender, GI Joe: Resolute), Sam Liu (Hulk Vs., Superman/Batman: Public Enemies) and other talented directors would be great choices.
Also, there should be several in-house writers, people like Dwayne McDuffie, Stan Berkowitz, Alan Burnett and Paul Dini would form the core and then could reach out to freelancers.
Also, keeping an in-house storyboard crew for each director to be supplemented by freelancers would be a great idea.
In terms of character designers, I think hiring freelancers would be a great way to keep each movie looking fresh.
All of these movies would be overseen by Bruce Timm and Gregory Noveck (as they are now) and enhanced by other regular producers like Sam Register, Bobbie Page and Linda Steiner.
The final part of the process would be to form partnerships with animation studios that have done great work in the past, such as Madhouse, Lotto, Moi, DR Movie and TMS (if they are still working on foreign projects, which I don't think they are).
I feel that this would also be a cost-cutting measure, maybe even leading to slightly longer movies.