I also suggest raising the action a touch... it doesn't have to be drastic... just an 8th turn on each saddle screw will help "tighten" the feel... as far as string guages... 9's can play pretty nice and have a decent feel... I've been on all spectrums of string guages and action specs... I...
I have no issues with the synthetic bone nuts... they sound just fine to me and they are durable... however, I have done a couple of nut replacements on two of my strats and I went with the Tusq nuts. They're decent.... FWIW... if you're not having a problem with the synthetic bone nut there's...