Firstly, don't get cross drilled discs, there's no need. Grooved or J-hook design is far better, especially for everyday use.
Given the choice, if you want larger OE brakes then use the Golf 7R setup as it's a few kilograms lighter than the Golf 6R/ Audi S3/ Lean Cupra R brakes and there's quite a few hitting the market now.
I run the Cayenne/Q7/Touareg 6 piston Brembo brakes on 350mm Mercedes discs (EBC Yellowstuff pads and Ultimax discs) and now I've used fluid that isn't f****d they are great. They have a very natural feel and are lovely for daily driving but when stomped on you'll be face planting the steering wheel if you're not careful, they really can stop the car at short notice.
Another option which I'm surprised hasn't been mentioned is the NQSBBK, using Porsche 986 Boxster front calipers on stock 312mm discs. This is a budget friendly yet track capable setup which you should consider as it'll be the best middle ground in your situation IMO.