Well after E3 I decided to reinstall Sim City 4 DX. Things didn't go so well, had all kinds of rendering issues and once I switched to software mode it still hitched up. Then I noticed Cities XL 2012 on sale on steam ($10) and immediately bought it as I had heard some good things about Cities XL in the past.
Reading a bit more it seems like there are some performance issues, most notable the fact that the game only uses one core and also some memory leak issues.
I've seen a few sites with mods, but being out of the Cities XL scene I have no idea where to start. Are there any good content or performance mods out there?