Addressing the OP, would you really save that much time with your suggested free for all?
Don’t get me wrong I have been, and still am annoyed by middle lane Hogs myself and fast lane cruisers can bothersome but then as said earlier its not a race, you need to think a little more “Zen” on the motorways if you plan to use them long term and survive.
The reason we overtake on the RH side only is actually to maintain the flow of traffic and mitigate accident risk to a certain extent; if there is “standardised” behaviour for each lane on the motorway then it makes it a more predictable environment where it is easier to judge what others may or may not do next.
Think about pulling out from the Middle -> Fast lane to overtake, momentarily your attention is focused not on what is in front and to your right (Where you actually plan to manoeuvre the car) but behind, in your rear wing mirror and/or maybe over your shoulder towards any blind spots, you expect the vehicles in the lane you are entering to be moving faster than you are currently, you also expect the opposite from the slow lane; slower traffic without anyone zooming up from behind, thus making it easier for you to speed up/slow down/exit/enter with minimal fuss and the main body of traffic moving at relatively uniform speeds, believe it or not actually most of the time this approach works (All of this is rather idealised I know).
Now let enact your repealing of traffic laws and see where it gets us…
The same bewildered Arses will still sit in the middle lane while “Boi Racers” like yourself flit inexpertly between all 3 lanes trying to make up milliseconds on their journeys, eventually either colliding with an A3 they “Didn’t see” pulling into the now re-christened “Undertaking lane” or just pile into the central reservation once they’ve worn all the tread off their Toyo’s…
I know people who never go in the outside lane normally because it’s “Full of Cocks” I have to say they aren’t far wrong really, it isn’t a race, as long as the traffic is moving you are actually making progress, then 90% of the population don’t really seem to mind if they’re doing 63 or 103 MPH the actual difference in arrival time between Averaging 70 (which the middle lane seems to most of the time) and Averaging 80 over say a 100 mile motorway journey is only about 10 minutes, and you’ll only waste the saved time pissing about finding a space when you get there anyway, so why bother?
You want us to drive like Yanks? They are Bloody useless drivers, their rules don’t help the situation either…