Surat Thani is really a pass through destination, people pass through the airport on their way to the East Coast islands, or, as I did, when I caught the night train to Phuket.
But since we were dropping off friends, we had time to explore the town and there's one thing well worth doing here.
When the sun goes down, there is a night market along the river, and in the middle of that market is a pier where you can take a boat out and see the fireflies.
It's better, far far better. There are many many places to see the fireflies and there are many more of them. I wish I could show you them, but fireflies don't like camera flashes, or laser focus lights on cameras and phones, and so you may not use any camera or phone on the trip. But that's OK, just enjoy it yourself.
Look for the illuminated sign next to the pier, the price was 50 baht per person, it's an evening trip that lasts an hour. It runs from 6:30pm till 9pm, they wait till enough people want to go, then the boat sets off, so start times for each trip are not fixed.
The same boat can be hired for a nature trip during the day, so we arranged that for a trip the next morning. (If you have a Thai speaker, the boat captain's number is 077205323). The nature trip is impressive too. Surat's river delta is unspoiled and very natural.
If you need a hotel in Surat Thani town, I suggest "Paragon Hometel". Which is more like a housing estate with town houses in it, than a hotel. It was clean, cheap and friendly.