How many quotes are you looking to memorize for each text(Medea, YOW and The Crucible)
I can't say for the other texts besides Medea since I didn't do comparative last year.
I would say going into the exam I memorise ~20-25 quotes most likely more then that if I'm honest.
With Medea, then are a lot of good short quotes that hold a lot of information such as "tuscan syclla", "lioness guarding her cubs", "everybody loves himself more than his neighbour", "I fear you", "to punish Jason will be just", "...child killer", "vile murderess!" and many more.
I would remember the key ones that everyone puts in their essay and maybe some specific ones like the animalistic quotes to show Medea is an outsider or ones that show Medea is different to other women.