There are so many ways it could be improved. No coupling you for the first week, newbies in for a minimum of 3 days before they're booted and every newbie coming in gets to speed date or the public choose them 3 dates, newbies always get first pick at recouplings, and those not chosen have to leave.
No bed sharing until you're an official couple, split the villa into a boys room, girls room, couples room.
Casa Amor could be different, make the couples choose before they even go in, either split and Casa Amor and they can't recouple again during their time in there or go home if they've found 'love'. No one will coast then with someone they don't really like.
There's so much they could do to spice it up and make it fresher instead of same tired old challenges and couplings every other day.
Also ban 'where's your head at?' and 'what's your type?' Allow real conversations and bring back smoking area and a reasonable amount of booze.