Thank you. To answer your questions:
1. No, there was no plan to add a gag ending related to it.
2. In short - both.
I planned it to be a long route where you as the player meet Akechi and Akiren while they were younger, and then based on your choices there it would develop your 'personality' (like the sun/moon route), which will differentiate the way you can answer to certain situations when you were older. It was going to be a different plot altogether from canon. And your choices to solely favor one guy or treat them both equally will influence whether you're going down the 3P or PvP route.