Here's my two cents (coming from someone making a game that has the most stereotypical of JRPG plots) Take a concept or story that generally isn't seen in JRPGs and make it into a game, utilizing as much of the gameplay and structure of a JRPG as you please. Just an idea ^_^
(And again this is from someone who is making a "hero vs evil overlord" story, so if you want to go more traditional, feel free.)