I'm making an fps right now, and I don't have everything about the game mapped out. I have some basic ideas in my head, and some basic mechanics done, like movement (still a wip but got basics down) basic enemies that don't do anything but can be destroyed, and a lot of the framework for my weapons system.
but I kinda feel like it's hard to get a feel for the gameplay is when I'm using prototype cubes and have no sound effects. For instance if I added a sniper rifle that was just a cube and makes a cube enemy disappear in one hit, it's not going to feel the same as if I had a sick sniper rifle model and added animations and camera recoil and sound effects and death effects etc.
But at the same time you don't want to do too much visuals during development because you are still working out gameplay and things are subject to change.
When do you choose to add basic assets/final assets to your game like animations, sound effects, models etc. and when do you feel like these things actually change the feel of the game and are needed for development?
(I'm going to do modeling and animations myself in blender)