This has been answered a million times already if you search but im not a rude spanker who will flame you for not searching.
Personally I think its a lot of money to be spending on shocks for a street car that will never really see any hard driving but its your money and they'll work perfectly fine with any springrate you throw at them. I'd recommend a 6kg Front/4kg Rear to start with as its stiff without being too hard for street but It's really personal preference.
As for ride height.. If you can swing the cash for coilovers then the adjustablility is worth it. Personally my car is dumped on it arse but..
A. My car isnt daily driven
B. I dont care about scraping my car over speed bumps and gutters
You don't really need RCA's but they do cut down on the bump steer you get when you lower your car. Look into an adjustalbe panhard rod as well if you want to run wide, low offset rims or you may run into clearance problems at the back.