Can’t say for sure as I’ve never built anything from scratch, but the speedster I’m modelling mine after (Richard Scaldwell’s GN JAP) seems to be doing just fine after more than 10 yrs on the road and track. No friction shocks either on his.
The wooden axle is interesting, but Morgans never had wooden frame rails. They had, until very recently, ash body framing which, as people are unfamiliar with this (once common) way of constructing coachwork, is very often misinterpreted as wooden frame rails. Early three-wheelers had small-diameter metal tube frames much along bicycle lines, and most four-wheelers and, I believe, later three-wheelers had steel Z-section rails whose lower, inner flanges bore the wooden floorboards. A better example of a wooden frame would be early Franklin:
And if you look really closely at the front axle, you'll see it's a steel axle with a wooden fairing. I can't imagine it made much of a difference...
Looks like the front axle is wood, but it’s steel. I’m guessing that is just some type of decorative “spoiler”, but the frame rails are indeed wood as all GN were up to about 1918 IIRC.
Do the simple stuff first. Work your way up. There is a reason they make steering dampers, and they aren't too expensive. Remember that bump steer and wobble are two different issues. Fix one, decide if the other is still a problem. Best practices are great, but sometimes you just want to fix the symptom. It it goes away, is it really a problem?
Don't have mega years of experience,...or opinion but, death wobble is NOT intrinsic to cowl steering. I chased it after many experiments with everything adjustable and worn, replaced the whole front axle, spindles, spring assembly, shocks...everything! Resisted the dampener band-aid until that was the only thing left. Dampener finally was a fix and at a small fraction of what I'd already spent. And as mentioned here, many builders automatically include that item on a new build with the more traditional steering systems. And bump steer. Don't even go there. If your car is safe and comfortable to drive, go for it. If you're not aware of bump steer, figure you don't got it and enjoy the drive and the cool factor of cowl steering!