I was an experienced whitewater paddler before I became a fisherman. I have been yak fishing for 10 years and the last 3 with a flyrod only. I have a sik and a sok. Both have their advantages. I do rivers and lakes, no oceans. One of the things that makes fishing manageable and really fun in a yak is understanding wind direction and strength and water current.

There are lots of ways to do this but I find the easiest mentioned above is with a light anchoring system on the ends of the yak with all the safety proviso's mentioned above. I typically only use one anchor at a time. I never anchor in a fast (or medium) moving section of water. By reading the water and planning ahead you can tell what spots you want to fish then you figure out where you and the yak need to be to fish those spots. It takes a little extra planning but learning how to paddle in river currents (and windy lakes) significantly improves results. I recommend taking several trips to learn how to best paddle primarily and fish secondarily. Also get out of the kay when there is a nice wading spot.

I did rent an inflatable and ran a fairly challanging white water river in colorado. That experience indicated that this boat should be fishable as well (as indicated above). The one I rented would spin very easily so that would have to be controlled as well. My kayaks are recreational so they have a v shaped hull. Spinning is not a problem in them.

Regarding colors I have seen big smallies that seem more spooked by noise than color of a boat drifting by.

BTW you can't catch any fish from a yak so don't bother.