Pretty simple answer. Do what they do in rugby. Stop the clock when the game stops for an injury. Sin bin players for a yellow. Pretty radical solution but it would eliminate both sides of the cheating/timewasting. No valid reason why either wouldn't work.
Sin binning for a yellow would stop any strong challenges from going in, really. Thus destroying the quite often aggressive nature of the English game that makes it so visibly appealing. Would be unfair if the tackler comes in hard but has every intention of getting the ball fairly, just gets beat by the man who nudges it on and clatters into him. It is a yellow, nothing more, but then he has to have a sin bin? Would end up with slide tackles not having much chance of existing anymore imo.
I don't like Sepp's idea. What if you have taken a knock, you have a dead leg that initially hurts a lot for 60 seconds, you stay grounded for as long as it takes to get your bearings, and then you are disciplined with a timeout. Seems wholly unfair.
I like the retrospective bans or yellows for outright dives with the player turning around and appealing it, or if they have playacted injured to induce harsher punishment for their opponent when really they are fine.
There is a problem though with referees and the fact they do not give foul often if the player stays on their feet. It goes for shirt pulling and a little nibble with the feet. It is never enough for one to go down, but under the letter of the law if it is a deliberate and illegal hindrance, it shouldn't matter how soft it is as it is there and has happened. The ref should be giving penalties for times when the player remains on his feet, despite a foul, especially in the box. So the players react by over-hyping the incident.
As for playing the advantage for penalties that is sometimes seen when it looks as if despite the incident a goal looks likely. I find that pretty annoying in incidences where the defender would have been sent off for it but have been saved by the guy that they tried to haul down getting up again to slot home. Example here:
If the keeper gets sent off there, its 10 against 11 and Ireland may have slotted home the pen and gone on to win the match, as it stood they go on to lose, despite that goal.
Think the referee's need to enforce smaller offenses better to stop players play acting, because they only play act because they are trying to overhype an incident they know otherwise they wouldn't get, even though it should be a foul. Also they do it to cheat when there isn't a foul, but I think their urge to do that comes from referees not punishing fouls often enough when they are.