First thing I did was finding a good deal on H&R's and once I installed them and got the 1" drop, the car handled like it should have with the "sport" package and factory rims... I would also look for a deal on a strutbrace, since I noticed how much it flexes when installing one... (BMW OEM is really nice...)
I didn't buy my XI to have a car to go offroad, and neither to have a car that would scrape every bump. I got my XI, because I like to drive it hard and still not worry about the few snowy days we get here. (If I wanted a track car, I would have gotten a Lotus.) So the 1" drop is perfect for me. Still good for everyday driving, just being a bit more careful with bumps etc.
I would keep my eyes open and look for a deal on wheels and get them after you have the suspension figured out.