We paid a premium to have a trip for just my wife an I, the amount wasn't large but WAS worth it. The first couple of places we stopped at were a high vantage point for photos of the Khao Sok national park and subsequently a 'Wat' dug into caves with it's own troop of monkeys. Neither were particularly of interest, the views, whilst great to the naked eye, required a camera and lenses that were beyond the capabilities of the small devices we'd taken. The Wat was small, one figure within. The monkeys were....well, monkeys. For both points, we'd got out the van, looked around, weighed up what was what and got on the move quite quickly (a nice option when you're on your own private tour).
We subsequently had a paddle along a river on a bamboo raft (highlight was the guy losing his punting stick deep in the mud), though there was a nice touch with coffee in bamboo cups (we got to keep the cups - nice).
Best part of this trip was the boat trip across the man-made lake (dammed up, Cheow Lan Dam) out to a floating village for lunch/swimming. Very picturesque, lots of photo opportunities.
Throughout the trip, drinks were made available to us, the driver was careful and considerate on the road, the guide (Bill ) was very knowledgeable of the Khao Sok national park and of the lake origins and background stories.
We organised our Hotel to Airport (Phuket) taxi/transfers too. Nice large, aircon car with bottles of water provided (courtesy of Marriott Hotel, not sure what the link there is/was). Price was good, much better than the Hotel transfer cost (we paid 1300 BHT rather than the 2000 the Hotel were looking to charge).