The control arms (wishbones, tierods, etc) are pretty easy. There are two per corner. In addition you will need different clips to route the brake sensors and also a new rod for auto-leveling headlights. I am sure all of that is documented in the DIY articles online. You are correct that they would likely not be covered under your warranty even though they are BMW parts. But they are also parts that I have never heard of failing so it should not be a problem.
I did the swaybars from a E92 M3. The front is easy to replace but not that much bigger than the stock 35/335 bar. The rear is a pain as you need to drop the subframe. About a 4 hour job start to finish for a qualified shop to do. Also, unless you have a LSD, I would not go with the larger 23mm M3 bar. It is too much bar for an open diff.
Feel free to find me at the next autox and I can give full details.