Movement is there, so is the game idea of going down, surviving etc.
But this thing is barelly a template void of any objective besides the skin unlock, which would be horrendous to grind for, since the game in its current state lacks a motivator.
Below is my take on this.
Toggleable sidegrades either as suits or as simply buyable and toggleable things (the latter would allow for free suit customisation)
Less fall damage, but higher health drop
More fall damage, but lower health drop (Marsonaut would fit, if you choose suits as the upgrade thingies)
High jump, but jumps consume energy.
And so on.
That way you keep this game as it is whilst giving players choice and the grind a meaning.