The best thing i can reccomend to anyone is put in the time and make the setup yours, get what YOU want out of the car and enjoy it.
+1
I have been working on an excel style spread sheet for my rb5 over the last couple of months. Trying all the setup options for the car, some better some worse, but the important thing is I now know the feeling of each change and now my local track setup is spot on, but when I go to other tracks I'm able to quickly adjust the car to my liking.
It's also a great feeling to learn and understand more about the car each race day. Very rewarding.