I've just put a set of 20" forged wheels with nonRFT, no issues. It's my 4th Bimmer with RFT that I've changed to nonRFT.
It's the first time I've had forged rims on the car. They are way lighter than factory (& stronger), which makes the car feel more nimble, improve steering feel, and feels quicker.
As for tyres, it's personal preference really. I tend to stick Michelin, Pirelli , Bridgestone, or Conti - as they tend to maintain the BMW steering feel. IMO Conti Extreme DW are hands down the best value (tireRack.com), I have them on rear axle and they offer fantastic grip. Pirelli Pzero (black or silver) have a really nice ride, I had PZB on my E60 and they made the ride more plush with good grip.