I have given two recitals on the Halifax organ at the invitation of Philip Tordoff and while the instrument has its limitations, my impression was of an extremely musical instrument that was incredibly easy to control. Modern aids may give you more opportunities to get just the right sounds, but with care, the organ is extremely easy to handle.
While the mixtures may have been altered, changing things back may be a retrograde step, many organs are changed and gradual improvements may be made, it seemed to me that the conservative changes worked.
However, I don't live with the organ, unfortunately, but I think Iam pleased that the Walker suggestions were not undertaken and therefore I was able to play a really fine instrument.
Having lived with two large instruments which had been given full blown "enlightened" rebuilds, we always bemoaned the loss of the old choir organ, or the solo clarinet and a decent open diapason. It didn't stop us using the new stuff though!