Pacific beaches are usually that salt and pepper sand and kinda murky water. Isla Iguana is a beautiful exception -- white sand beach. When I went my friends we had it all to ourselves. It was post card perfect. If you have any Blue Lagoon fantasies and anyone that looks like Brook that is a great place to be. Pedasi where you will have to catch a boat is nice but really not much going on -- bring friends and it can be fun.
Remember though to keep Carnival in mind. The party is not far away and Pedasi may get booked. And if you do get a place down there and pass through the Carnival towns and see all the people going nuts you may be tempted to hop off the bus and join them.
Please let us know about the other places Playa Venao and Isla Canas. Never heard of them. Where did you hear about them?
Great new places off the beaten path are popping up everywhere and the guide books can't keep up. Beats most places in Costa Rica if you ask me. The Lost and Found is in the Fortuna Forest Reserve along the highway between David and Bocas so it is a stop in the cloud forest on your way across the Continental Divide -- amazing.