I have an all Audio Research system. If I didn’t It would be all CJ. Yes I would highly recommend the LS28SE, or LS28, or LS27SE... how ever far back you have to go back. I have the Reference series.
A good friend whom I helped to choose his system has an LS28SE. It will a bit more detailed and neutral, but musical like your CJ. If that appeals to you.
I feel that the warmth of your CJ helps to offset the more neutral lean Manhattan.
I’d put your equipment and proposed changes into ChatGPT and evaluate to sonic characteristics of the change. It typically does a great job.