That's a super idea. Currently I have to manually prepend my custom #{prefix_highlight} to status-left every time I create a snapshot. I imagine many, or most, people would like to append it to status-right, after tmux-prefix-highlight's readme.

Not sure what the option should be called then, affix perhaps?. Maybe it could have 2 sub-keys: content and location. The former would be the thing to print and the latter would let you specify which end you'd like the content to be on, left/right; before/after; prefix/suffix.