Did you look at the sway bar links? When they wear out you will get a lot of "clicking" type sounds when you hit bumps. They are a common problem area on older BMW suspensions but the good news is they are fairly cheap and easy to replace.
It wouldn't hurt to check, but if a brake pad was loose I would suspect that under braking you would have a lot of vibrations and shaking coming through the steering wheel. Do you have a strut brace by any chance?