To make class balancing easier it would be nice if there were a way to toggle off attacks on player pets. I wonder if this is even a possibility or if it would cause nightmare UI coding problems (aka lots of “you can’t attack that target” in combat spam.)

I think a toggle is overdue, but nerfing pets is not the answer. Pets are part of the “build” and even a great feature to potentially buff (if done right) but the game needs a way to make interface frustrations not part of the combat with pets. This would better allow ZOS to keep the balance manageable.

Ever heard of tab targeting?

just kite around them and don't play too risky all in, also just as PhantomOcelot said tab targeting really saves you effort and time