I'll be honest, I don't think Black Mage is "okay" in any shape or form.

As such, while I feel the changes are negative, they cannot really do any damage. The job is in shambles, and has been since Shadowbringers at least. I would vote for ripping the job out entirely and going all the way back to the drawing board, keeping nothing but the motif of "Fire, Ice and Lightning". Scrap all current abilities. And the idea. Just re-do it from the start, "Big badaboom caster", no further limitations.