Just can't kick my Koke habit

Would a mini x or i9s work there? ( think truck bed/ short boat / impulse fishing )

Sure, that sounds pretty cool, Fil (YAKBUM) organized one last year but I don't remember the time frame...pretty much everyone caught fish.
I fish American quite a bit in the fall through spring, it's also a great smallmouth, rainbow (triploid), cutthroat and perch fishery...but as Lee mentioned, it does get full of stupid people in power boats when the weather gets warm.

Would a mini x or i9s work there? ( think truck bed/ short boat / impulse fishing )

Sure, why not? This time of year you don't need a downrigger or anything fancy...just run a sliding egg sinker (1/4-3/4 ounce depending on how deep the fish are) and bead above a swivel then about 24" of leader to a flasher and then an 6-8" leader to your hoochie/wedding ring/dick nite spoon. Tip your lure with gulp maggots, shoepeg corn or a piece of worm and add some anise or garlic scent if you want...troll around 1.2-1.5mph...reel in fish...repeat.  A really soft rod will increase the number of fish you land...keep your rod tip down and use a slow steady retrieve...don't give them any slack.

The first hour of daylight is the most productive and the fish can be caught just under the surface down to 15' deep...as the sun rises, the fish move deeper and the action slows down a bit. The western shoreline in front of the VA hospital, the large lake basin north of Silcox island and the northern shore in front of the Lakewood city boat launch are my go-to areas and always hold fish.

A really soft rod will increase the number of fish you land...keep your rod tip down and use a slow steady retrieve...don't give them any slack.

I agree with Nangusdog that a slow steady retrieve is important, and I try to keep the kokanee underwater until the last moment when I bring it up to my net.  If you pull a kokanee to the surface, it's likely to thrash around like a hummingbird and throw the hook.  I think that if you include a small rubber snubber in your set-up to absorb shocks from thrashing fish it'll increase the percentage of kokanee which you get up to your kayak.  I think the best place for a snubber is right before the leader which runs to your lure.  If you install a snubber above flashers or cowbells, the drag from the flashers or cowbells will stretch the snubber and reduce the amount of shock absorption which it provides.

I like to fish for kokanee with a downrigger, so when I find a school of kokanee I can run my lure right through or just above the school.  It's a pretty precise method of fishing.  Because I'm used to using a downrigger, fishing with leaded line or sinkers seems unacceptably random and unpredictable to me.  But if you don't have a fish finder and a downrigger on your kayak, leaded line or a sinker setup such as the one which Nangusdog described is the way to go.

Great report. I wish there was a good koke lake close to Portland, that looks like a lot of fun!