Glad to hear you made it to (and enjoyed) Iriomote and Taketomi. I had the same experience you did trying to get to Iriomote; ended up detouring to Ohara, but being able to go back from Funaura. So I guess the wind issues are quite common.

There are also places on Iriomote offering kayak tours that take you through mangroves upriver to various waterfalls. I did one of these, and on the way back, since the tide had gone out, we were able to walk around on the mud flats and check out the mangroves and various little critters up close. Pretty cool. The guide was originally from Hokkaido, while the owner of the pension I stayed at (and his friend who ran the dive/snorkeling shop) were originally from Yokohama... I wonder how many people who are born there actually stay.

I actually spent two nights on Taketomi, which is recommended only if you have a high tolerance for doing absolutely nothing (after a few days of kayaking, snorkeling and bike riding on Iriomote, I was happy to kick back!). The scenery is gorgeous on a sunny day, as you mentioned. At the minshuku where I stayed, I met a guy from Tokyo who visits Taketomi some ridiculous number of times a year.... it's nice, but there are other places in Japan I'd like to check out as well.