Stayed there with a BKK WG follow-up freebie years ago. Used to be a lovely quiet, quite exotic, beach and little else, a few peaceful (and cheap vfm) guest houses, that sort of stuff. Now it’s more citified. In case you find that’s not your cup of tea, the train south as far as Surat Thani goes near the ferry to Ko Samui, which is a bit more out there. I got a wood cabin on the beach on the north side of the island. A sleepy village, nearby boats to legendary Ko Pha Ngan, a few punters in the excellent (and only) bar and when you need a fuck you just hire a moto into town (other side of the island, full of yanks), get a carry out or fuck her onsite. I’ve only done the train on the return trip but it doubtless runs both ways. Also avoids the horrendous prices of airfares between Ko Samui and BKK.
Just thought I’d throw it in. But enjoy your holiday!!