Koh Larn. Yes, two weeks ago, I went with friends to visit this tourist-trap.
The ferry over took two tries at making a mooring, both failed badly. The ferry was going up and down on the swell whereas the concrete pier did not seem to match the rise and fall of the ferry. I slipped and fell, fortunately on the rubber tyre the ferry was using as a buffer. Landing on my arse, I dislocated my right SI joint leaving me barely able to walk let alone explore the island.
On the return trip, we got to within a few hundred metres of our target Pattaya pier when the propellor-shaft bearing gave up the ghost with plenty of noise and smoke, leaving us adrift. The Chinese tourists stampeded the buoyancy vests whereas previously they had been totally indifferent. <Grin>
Another ferry eventually towed us into a mooring and we trans-shipped in a still bumpy sea.
On the plus side, it was amazing at the speed with which maybe 2 dozen jet-skies came racing up to see if they could be of assistance.
In summary, the authorities definitely need to move on the wharf facilities at both ends. Pattaya wharf it better than Koh Larn but there was never a gang-plank in sight. The Koh Larn disembarking and embarking was down-right dangerous - I could just have easily gone down the gap between concrete landing and the bucking boat. I got lucky, though damaged.
For all those "gentlemen of a certain age" out there, I strongly suggest there are other ways to get an adrenaline 'kick' than by going to Koh Larn. The youthful and sprightly might want to try their luck.