I use short fly rods from my Commander kayak, but I’m standing 98% of the time. I think a shorter rod is easier to manage and easier when landing the fish. I haven’t had a rod over 8’ in my kayak in years. I use my kayak mainly for inshore saltwater, but like to fish out of a Jon boat for bass, catfish and sunfish, also using short rods.
I like softer action rods for various reasons for the freshwater scene and sometimes even in the salt. I’ve had a lot of fun with the Cabelas CGR series and they are a deal when they go on sale. The 7/8 is a good rod for bigger deer hair flies and the 5/6 and 4/5 (I don’t think they make it anymore) are good with lighter, more aerodynamic flies. I haven’t tried the St. Croix. My wind rods are a 7/8 and 8/9 G.Loomis Short Stix. The CGR and G. Loomis are the opposites, with the Loomis rods being extra fast.
To me, long rods are good for deep wading and some guys like them when sitting in a kayak to prevent the fly from hitting the water on the backcast. Long rods might be better at distance casting and on the water mending stuff that’s done for cold water trout , but I don’t run into long distance casting out on the lake, marsh or bay or do a bunch of mending for local fish. Short rods swing lighter in general and have a lot of built in accuracy. Less fast rods let you keep the rod loaded longer to let you influence the cast longer. That’s my experience anyhow.
http://www.ginkandgasoline.com/fly-fishing-gear/graphite-vs-fiberglass-with-tim-rajeff-video/Don’t over look fiberglass. There’s more and more of these showing up including some new shorter ones from Echo. Fiberglass protects tippets well and bends so well. When a big fish suddenly dives under your kayak, you will appreciate glass. It’s hard to break glass rods, too.