I use the Typing Transformer plugin as a makeshift auto-correction tool.
I have tested it on 56000 lines worth of rules and it works fast. The plugin also works on mobile (where I think most people would still use their keyboard’s auto-correction features).
I write in a native language that uses many compound words (like German) and is agglutinative, so I need to put spaces before and after both my “BadWords” and “GoodWords”, but it is less of a problem in English.
I cannot recommend it enough.
I also have two vast dictionaries (English and my native-language one) that I use with the Various Complements plugin, which unfortunately doesn’t do auto-correction.
The two plugins should sort of be merged into one.