You’re right that Ayer’s original vision most likely not very good. It baffles me to no end on why he thought Echantress was a better villain to use than Joker. Suicide Squad’s plot should have been a race against time to stop the Joker from executing evil schemes(maybe it’s a bomb that Joker plans to unleash on the city or something) and about Harley Quinn’s liberation from the Joker’s influence.
That would’ve been far better than whatever the heck that Enchantress garbage was about. Honestly what was Ayer thinking?