With the very fine work you are doing, I'm not sure I would do iron on. Definitely, if you do, use only Ultra-Cote or Monokote. Also check the finishing threads for putting Monokote on top of monokote without heat - there is a fluid for it. And I think (memory) water works. However, I've notice your work - it's great. I can't imagine that iron - on is better or even close to equal.
Allen,
I've been following the likes of "Great" Dane and Fred's Cesquim's work. Both of these modelers do the iron on trick like magic. Looks like you also have it mastered.

Fred actually incorporates painted colors and finishes in a two part auto clear to protect all applied colors and pen lines.
The "Jury" is still out, but Fred says he saves time, effort and weight with his iron on application system.
If I didn't already have some coats of clear dope on the ARGO II, I would certainly give Fred's system a try.
I do have another model in the works that has absolutely no dope on it.
I plan on keeping it that way and will give that model a try with iron on material, as Fred does, that's prepped for paint applications and auto clear.
Have you seen Fred Cesquim's work?
Nice model Allen and thank you for your kind words.
Charles