External sound cards have the advantage of less electrical interference, but usually the internal ones have external power not coming from the PCIe slot so it isn’t a big problem. Asus left the market leaving you with good old Creative Sound Blaster again. Choose whatever your budget allows, the two upper tier ones just differ in accessories, but that might have changed. And AV receivers the same, I am not the up to date audio guy what is a good deal. Just try to stay >120 dB SNR on sound cards for high end.
Ubisoft had many long standing issues, but disowning The Crew users was the worst possible move they could have made in their already dire situation.