One of the under appreciated aspects of chair buying, in my opinion of course, is what you weigh. Generally the materials and construction which expect to flex and conform do so within a set of limits that the chair designer had but may not have put into the spec. You can both be too light for a chair and too heavy. That is why actually sitting in the chair is something you might want to spend some time doing if you…
While I like Herman Miller (especially Embody), I am really opinionated about chairs. After trying zillions, I think those chairs that are quite firm and promote active seating and position variety are the best ones.
There is a quite famous Norwegian designer, Peter Opsvik, who has designed a few great chairs for Håg and Varier: Capisco, Gravity, Actulum, etc. All his ideas are well explained in a book [1]. Basic models are relatively affordable.
Aside from the Scandinavian chairs from Opsvik, Aeris produces some nice active seating chairs and stools. Other alternatives are mentioned in this mega review [2].
Very recently, Ikea has released a stool that follows the same active seating principles [3]. Quality and price are superb.
[2] https://www.nerdgranny.com/review-ergonomic-chairs/
[3] https://www.ikea.com/gb/en/p/trollberget-active-sit-stand-su...