Gotcha, still a very nice game overall and i wouldn't mind playing more of this If you continue the work on it too, as well the idea of a story for this game is there too just with the general theme and such
If you ask me what else i would add to this game it be this:
-FPS of Weight Gain when damage, to give an idea of WG but act as a 2nd Sign for the Player
-All Enemies are unique, like different genders, weapons and WG, like how Classic Dooms Are
-Some Items being unique outside of Healing and Armor but i would image this being abit more complex to do