Both Race 07 and rFactor is a good choice for online play, especially if you join our club! For offline play Race is better. Also it has a lot more default content, made by Simbin, in quite good quality. rFactor is much more a mod based game, you can find a lot of quite unique things for it, but AI isn't that good in that one. Race has weather, rFactor has night racing. I believe GTR 2 has both, and I'm sure it has some great AI and nice quality content too (although only GT cars as default content), just like the other Simbin games. Unfortunately GTR 2 only crossed my life as a demo, I have all other games by Simbin. The only thing I'm not sure about GTR 2 is the online part, I don't know how many people play it online still. Or there's GT Legends too, it has some events here too at the Historic racing club, if you like classic cars that can be also a good choice. (but GT legends doesn't have weather again)
As you said you like WTCC however, I would recommend Race 07 and it's addons, as it has a lot of touring car content, and a lot of touring car events in the club!
