Hey, i don't know if anybody has done this but I'm going to send a request to Rockstar with this forum post linked inside, I have already made numerous requests with my Social Club Account, maybe if a sh*t load of people send this in a request ticket R* might actually consider these tweaks that would really enhance the Free Mode experience.
Even if you don't think it'll help, I encourage you to link this in a suggestion to Rockstar's support site.
Edit: Just saw the OP that this was suggested to R*, well hopefully more won't hurt, hopefully this will get more attention!
Another idea to improve GTA Online, perhaps not only the Freemode, would be the addition of boiler suits/coveralls/jumpsuits into the game for criminal purposes, like masks.
My vision for this is that you would be able to buy one of these suits like in SP for the Blitz Play mission, and we would be able to put it on and take it off from the interaction menu just like masks, glasses, hats, etc.
This suit would work similar to masks and alongside them, meaning if you got 4 stars with a mask and coveralls on, you could break line of sight, take off the mask removing 1 star, take off the coveralls dropping another star, leaving you with 2 stars from 4. There would probably be an animation for putting it on, taking it off, similar to taking off a parachute or something. You most likely wouldn't be able to do this within a vehicle so it doesn't seem like it'd be overpowered, but just incredibly useful.