Looking for someone with game design experience, for a real life running game, meets base builder

I'm building a game with a hexagon map that is created over the player's city, that encourages people to go out running. The runs in real life are mapped on the game map on which they can get points in areas, pickup loot, ...

The actual game has to be decided, and for that I'm looking for a partner who has experience in Game Design (not the visual design, but the actual design), although experience in visual design would be a plus!

I'm based in Belgium. Let me know if you're interested!