Help with my game

I am currently in the process of making an open world FPS game using Blender and Unity3D.

The main plot in the game is that you are a genetically modified assassin, working for the bad guys. They try to get rid of you (kill you) , and you escape. You Irvine in a nearby city and forest, trying to find the people who did this too you.

The main reason I am posting this, is I am just a bit stuck for ideas or little things that YOU would love to see in a game.

Thanks for reading this and reply with suggestions or help if you so wish.

Whats the time frame for the game?

Modern and not futuristic, but advanced technonlgy. Maybe 2025

I recommend to try Deus Ex human revolution you might get some art direction ideas