I believe everyone should be encouraged to fight on their feet for the most part. Even more annoying than proners, IMO, are bunnyhoppers. It’s not that they’re hard to kill, quite the contrary. A jumping player is a predictable arc and an easy kill. No, the reason I dislike them is because they believe their best chance is to hop around and spray, hoping that if they can avoid enemy fire long enough, they will eventually land enough shots to make the kill. This isn’t skilled gameplay. Players should be encouraged to improve their aim so they can win on their feet. This leads to more skilled players and better competition.
So, jumping should send accuracy completely into the gutter. W:ET does this very well. Only the most green players bunnyhop in W:ET, because any player who’s been around a while realizes what a poor “tactic” it is.
While on your feet, spread should be kept to a minimum, so that skilled aim is rewarded.
As for prone, it’s more difficult. Sure you could just give proners horrible accuracy, but that’s completely illogical. And an “accuracy delay” like that offered by ETPro is rather useless to prevent someone from proning at a distance and laying in wait. The effects would have worn off by the time they shoot.
The only way to deal with prone is to make it available only to slow-firing weapons such as snipers. But I don’t think this is how ET:QW handles it, so it will almost certainly be a cause of whining. One possible solution would be to disable turning while prone. Lay down on the floor and try to turn while firing an imaginary weapon. It’s nearly impossible. With a limited firing arc, proners could be easily flanked and would be have to get back on their feet to counter it.