Considering that i) as @Tony Djukic put, “depends on how complicated the site is and how much of it is worth keeping around” ii) pain is something without an objective way of measuring iii) there will be some pain (and you acknowledge it). I say: just rip the Bandaid and go with option 2.
Evaluate if the website really needs the features and functionality the plugins provide. If so, add them progressively later. If the side doesn’t need the features it has today, you just got done and have a clean(ish) slate, and it may even be less painful than you thought.