Hey all, I've been lurking/reading CAP since CAP 4, and am newish to the OU battle scene. First forum post now too. That being said, I'd like to contribute constructively.
-Wouldn't Electric/Grass also have some abuse potential on a rain team? Sure, it can help out sun, but the simplicity of giving it thunder and spamming it on a rain team is probably very appealing...
-Personally, I support Ice/Fighting. Out of the 4 weathers, it seems like sun could counter that mon the best(fire moves), where it's rock neutral and can do some heavy damage on sand teams(ground types?). Using a good ice/fighting could also let us offensively take care of Heatran and Dragons. In addition, if we make this mon relatively powerful on both sides of the offensive spectrum, speedy, and even a bit specially bulky, we could simultaneously be offensive, and not be mauled by rain or the Latis so easily. Also, this is Stealth Rock neutral right? I'm really liking Ice/Fighting.