What are your methods to make decisions about the direction you want your game to go?

Hello there!

I'm a junior gameplay programmer with a little background in game design working on a little project of my own. I'm in the very early stage of development and I struggle to choose the direction for my game.

I'm currently at a crossroad where I see several possible directions for my game but they are mutually exclusive. Since I can't seem to find a way to pick and choose, I was wondering what are your methods to choose what is best for your game?