Hey thanks.
That's one of the advantages of the Pico-8 platform is that you never have to worry about whether your PC is fast enough.
Yes, I'm working on an update with a few more tracks. So far I've added Spa Francorchamps, old Hockenheim and started building Monza, which will be the 6th. I may add a couple more after that.
And I'd like to add a championship mode, to add a bit of depth to it.