I got my father-in-law a pair of the 706v speakers with Focal stands. They sound pretty good at that hight and it was likely an intentional choice by Focal to make them that height.
My 836v speaker sit much taller and also have a great tweeter sound so I'm not sure that it's really critical beyond personal preference.
714v is 35-7/16" tall
716v is 37-3/8" tall
726v is 39" tall
836v is 45-3/16 tall (the tallest Chorus series speaker)
705v is 36-3/8" tall including 24" stands
706v is 39-3/8" tall including 24" stands
The tweeters are all mounted the same and should be equal distance from the top. There is certainly a range of tweeter heights within the Chorus series speakers. It seems that if the tweeter height was extremely critical they would consider making as many of the speaker have a tweeter at the same height as possible.