Paul:
Your panel looks very clean and neat, like a certified, production airplane. I like the layout a lot.
I've got one one comment about switches. I don't know about you, but I find that switches are easier to find when they are set apart in groups of no more than five, instead on one long string. Human-factors engineers have done studies, and they've found that the human brain works best with smaller groups of objects. Even a half-inch between adjacent switches is enough to set the groups apart. If a long string is absolutely necessary, it's a good design practice to color-code the levers with rubber boots, which would also serve to visually "group" them.
Some people tend to group switches based on function, i.e., lights (position, strobes, landing lights, etc.) grouped together. That's good, but I also try to group switches based on Mode of Flight when possible. For instance, before every takeoff, you turn on the strobes and the boost pump -- and after you clear the runway on landing, you turn them off. So you could group those two switches together.
You can also group things based on how much you use them. "Emergency" or seldom-used switches (Essential Bus Standby Power, Passenger stick-function disable, etc.) can be put out of the way, and/or guarded.
In the military, we used to do "blindfold cockpit checks," to see how quickly and how easily we could locate certain controls and switches, without looking. With a row of a dozen identical toggle switches in front of me, I'd be hard-pressed to remember which was the Pitot heat, which was the Aux Battery and which was the Fuel Pump, just by feel or memory.
Just some things to think about.
Keep pounding those rivets! See you at a fly-in someday!