In addition to Toukiden 2's Takashi Morinaka and many more, 4Gamer's big year-end game developers interview featured a chat with Idea Factory's Norihisa Kochiwa, who teased something in the works. According to Kochiwa they plan to announce a new game in 2016 that will feature "surprising" character designs.
Here's the excerpt:
"We're working with everything we got for a new title that will be announced in the first half of 2016! … "Their character designs will also be surprising, so please look forward to that!"
Kochiwa added that Idea Factory is also working to prepare more titles for Compile Heart and Otomate, so we'll have to see what they have cooking for 2016.