This is the type of fishing I do 90% of the time. To me, a 9 foot, 8wt is the best all around rod. Any longer, and you have trouble landing the fish and much shorter, you may have trouble keeping the line off the water on backcasts (although this could be overcome with proper technique). I like the shorter bass rods, but not particularly for kayak fishing. You are low on the water and it is already hard enough to generate line speed when casting from this position.
As far as line weight, an 8wt will allow you to cast larger flies in the wind. It also has enough backbone to land a big red in a reasonable time. I often fish a 6wt Scott Heliply from the kayak when there is no wind. For a 6wt this rod has plenty of backbone.
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