OmniDiff is character based by default. It will only highlight the changed characters. I suppose I could add an option to additionally highlight the line as well. Thanks for the feedback!

As for packaging. Unfortunately AUR is closed at the moment due to spam. I can add brew commands for Linux, happily.

In terms of “better”. It’s actually somewhat complex, but a simple way to think about it is that if you move a function up or down in the same class, text-based diffs paint that as “Deleted here, Inserted there” where ideally you would want it to say “Moved”.