I don't know what your mileage is or your driving conditions, but for an E36 that old, definitely change out the rear trailing arm bushings, if you haven't already. Also replace the rear shock mounts. The front strut mounts don't wear as easily, so that would be your call. Then the front control arm bushings. Check your front ball joints as well (outer & inner), but it would be a lot easier to change out the whole control arm, as they usually come with the ball joints pre-installed.