Sorry I have no recommendation to give.
I have just done some basic cheap fishing, e.g. 1000 baht tours with a group of friends. We were e.g. 10 people and just 2 people could fishing at a time while the others just enjoyed the trip and the sea/sun.
We got a new barowner in Soi Eric this month and his new bar, Let's go bar. They also arrange fishing and diving tours and you can book at the bar. You can always check out their website
www.letsgocharter.com
But there are a lot of companies offering similar tours.