ACR is hardly realistic though
Project C.A.R.S shows some small promise, but very much a work in progress and not worth it right now imo.
rFactor 2 is there as well, still a work in progress but much better than CARS so far.
But the king of sims right now is iRacing, it aint cheap though with a subscription + content model, but for that money you get, imo, the best simulation there is with laser scanned tracks which are superb, but the sim itself whilst under constant development does lack some of the 'nice' features.
As for Rankings, not sure CARS or rFactor 2 really offer anything? iRacing provides you with iRating (based on how good you are, finish in the top half of a race and you generally gain some, finish in the bottom half and you generally lose some) and Safety Rating which is how clean you are, it's a non-fault system so any contact between cars affects both drivers but that evens out over time if you're actually clean.
EDIT: And just finished reading the post

unfortunately very little in the way of car customization in any pc sim really, setups you can do in the 3 above, paintschemes in iRacing and I believe rFactor2 as well, but no changing engines or anything.