My dear wife and I are on the same path, but a year ahead of you, we are gonna downshift at the end of ‘22 and jump on the Viking world cruise. We think it is not only a good idea but a great idea. Life is too short to keep spinning.
I would recommend you look at them, on a per deim basis they are very similar cost as the others, but seem to offer more. the Viking loyal folks have a lot of good opinions and even better advice.
I also wrote a bit of why a world cruise and why Viking on my blog.