I've written a VN fanfiction for FSN intended to be done in the style(structure) of the famous Persona series. You should be able to social link with different characters, and with luck, get the appropriate stats and social link combinations to get the various endings.
I've not yet decided whether or not to include a battle system. That's fully reliant on whether or not I get a good idea for the battle system. Currently I do have *some ideas, but 2 problems. 1. An extensive battle system is a crapload of work. 2. It's hard to make a simple battle system interesting.
Feedback, etc, are welcomed.[FSN-VN] Holy Grail War: Social Link Edition http://typemoon.us/visual-novels/holy-grail-war-social-link-edition