Open galaxy sandboxgame for me. Visit different worlds, hunt their most dangerous inhabitants. Customize your gear depending on your prey, kinda like you adjust your gear in Witcher III depending on what you expect to fight.
Let the setting be in the future so that humans started to explore the stars and a lot of freshly established colonies have a frontier kinda feeling.
Hunt on jungle planets, desert planets, swamp planets... you name them.
Sugar on top, have some predator on predator conflict in it.
If that's to much to ask, I would gladly take one in the style of the Friday the 13th game like many suggested.
A bunch of weaker characters have to work together to bring down the more powerful one, while that one has to pick them of one by one before they get too organized.
