I totally agree with everyone here. There's racing to be had with an S1 licence, but it's very limited and the S2 licenced racing will blow your socks off. I particularly recommend Birder's ConeDodgers GTR servers and league. I hear all good things, and love racing on the public servers! I love the GTRs, but you can't use them with just an S1 licence.
Upgrade to S2, buddy! You won't ever regret it! There are SO many more options available to you in S2