Option 2 is another good idea. I'll probably go that route in the future since I've got a cargo carrier also. I've determined the maximum roof load with the two factory crossbars is 5 sheets of 3/4 inch walnut plywood - 335 pounds. The crossbars are fine because the load is spread evenly across them, but the front tips of the side rails lifted up off the roof 1/4 inch

. Fortunately they sprung back in place when the load came off. I wish there was a center crossbar to even out the load on the side rails better. Two just aren't enough.
2002 X5 3.0 378,500 miles
2014 428i 67,700 miles
2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles
1970 Firebird Under restoration