Firefly
This first suggestion may be an obvious choice for some – but for the many fans of Joss Whedon's beloved-but-tragically doomed space western, it's not one they'd likely turn down. Telltale have demonstrated their skills when it comes to balancing action and comedy with Tales from the Borderlands, and just like Tales, it'd be another great opportunity for the writing team to bring their comedic chops to bear. Knowing the passionate fervor of everyone involved with the series, it's hard to imagine a number of the series' original cast not jumping on the opportunity to reprise their roles.
Firefly's infamously short run has left the ‘Verse virtually unexplored – and Telltale's episodic formula could be the perfect vehicle to continue what Serenity started.