Since the issue seems to be affecting the highlighter differently based on which mode it is using, having different defaults for the modes could be explored.
WORD may have the new defaults as it has little effect on performance and it creates nicer highlights. SENTENCE should have the defaults that produce reasonable performance. The docs could document this while also mentioning that the UH's performance is highly dependent on the underlying Java String/Text? Iterator. One can argue that having different defaults based on mode is confusing. In this case I think the defaults should be changed to have the SENTENCE mode perform better. Maybe the options for nice highlights with WORD mode could be put into the docs in this case as some form of an example. As long as I can use the UH with nicely aligned snippets in WORD mode I'm fine with any defaults. I explicitly set them in the config and in the queries most of the time anyways.
