I really don't like the "Mind Battle" trope where the Doctor just thinks really hard at someone to defeat them, and that's basically all this story has.

The Doctor seemingly having no issue with Brimo being returned to eternal torment seems rather out of character, especially considering he did not allow Chronos to sentence The Master to essentially the same punishment. You imagine he would be more lenient on someone he knows nothing about outside of the brief confrontation in this comic.