Floating elements are not just good in macro lenses. They help maintain image quality in all lenses that have difficulty doing so otherwise over the range they are supposed to be used in.
Many macro lenses are of a design that isn't very 'scale sensitive', i.e. they work great over a very wide range of distances. And they may not be in need (if at all) of floating elements as much as some other lenses, like retrofocus wide angle lenses and zoom lenses (zooming itself is achieved by 'floating' elements, but image quality suffers. It can be kept up by 'floating' more elements.)
The original question, i believe, was whether it was worth to spend the extra cash needed to get an FLE version of a focal length also available as a non-FLE, 'normal', lens.
The answer to that depends on how good the non-FLE is. The gain in performance achieved by adding floating elements in the design may be small. It may also be quite significant.