the only way to stop the stone chips is to never actually use the car!, or have the nose covered with the protective film (paintshield, ventureshield etc) and get some bigger mudflaps to protect the lower rear doors from flicking stones up. And tailgating other cars is a big no no too.
Second that about the curbs. First thing I did when I drove the car home was to scuff the alloy on the curb as I parked - damn 18" wheels!Never had a problem with stone chips in the year that I owned it but I did have a BIG problem with bugs. I mean that thing is a born insect killer. If you doing long trips in the summer invest in some bug cleaning spray and keep it handy in the boot.
If you do happen to catch the nice big black wheels keep a small tin of smooth black Hamerite handy with a small paint brush and just touch the paint up.This stops any further damage to the paint work until you can get it repaired , if the damage is to much then it covers it ok and you can live with it.