Sounds like a good spec to me. Silver's a good choice - darker colours definitely get dirty quicker.
Did you test drive the manual 335i, and how was it? Presumably pretty good if you decided to order one :-)
Which wheels are you getting? As you can see from my sig, I went for the 18's but they don't feel much different at all from the 19's on the demo car.
2015 F32 430d M Sport with M Sport Plus and Pro Media packs - Winter wheels and tyres
Previous BMWs: 2012 F10 520d M Sport, 2009 E92 320d M Sport, 2006 E92 335d, 2004 E60 530d, 2000 E39 525d, 1997 E39 523i