Breaking figure order by referencing a figure in a later section
Certainly, there are vastly different personal preferences among readers and authors alike. Unless you can establish a pattern that matches the preferences of the reviewers1, you will have to go with what you (and your co-authors, and others who you ask for advice) think makes most sense in the concrete case.

If you conclude that Figure 14 is best left where it is (between Figures 13 and 15), because e.g. Figure 14 is descussed in depth in a later section while the mention between Figures 5 and 6 is only a side note, it sounds correct to me to leave Figure 14 as Figure 14, even though it is mentioned earlier. (More concretely, it would sound extremely cumbersome to show Figure 14 early in the paper between Figures 5 and 6, and then, later on, where the figure is discussed in depth, force readers to constantly switch between pages while reading the text.)

In that case (if only to appease reviewers who think otherwise), it could be adviseable to explicitly acknowledge the side note character of the early mention of Figure 14:


  This can also be seen in Figure 14, presented/discussed below in Section ... .


1: Note that I consider it at least somewhat ethically questionable to deviate from what might be most conductive to the readability/comprehensibility of the paper just to please a specific small set of reviewers (who might not think in terms of what supports the reader's mental model in the concrete case, but rather based upon "general formal criteria" such as "Are figures ordered by the order of their first mention?"). So, it is up to you whether to actually follow such a pattern.