On the X-brake front - mine rattled and I could never get a good adjustment as described above: adjust the cable so the bite was good and strong and the pads were too close - back them off and it'd fail the MOT.
However - I stuck with it and fixed the pad rattle by following Si's silicone instructions to the letter. Did it inside with a vice.
I also re-set the arm on the splined shaft, moving it by quite an amount, and that resolved the pull issue. The pads could sit right off the disk with no tension in the cable - but when I pulled the lever they pulled on much stronger.
Now it's fantastic and I wish I'd done this years ago.