Actually I was wrong; Eibach makes springs that go up to 1.8 inches lower.
That or you can get coilovers and drop as much as you want until you start to rub somewhere -- which is what I'm doing: probably getting them installed Friday.
As far as offsets go. Around +40 is about what the 3 series cars run; you can actually run 20 (5, 7 series offsets -- sticks out 20mm further), but you have to run stretched, narrow tires (225 or maybe even 215) to clear the fender lips.
I'd personally go with silver, but your choice really.
Whatever you get, you wont go wrong.
Hope that helps
ps. If you decide to sell the wheels that are on your car right now, let me know -- I want a set like it (given that I like the price).