I might not be a Know-It-All, but I know enough to get my planes painted.
As in most everything concerning paint, the best decision as to which kind of materials to use is dependent on the specific application. The question specifically stated the intended use of "ordinary 12 minute" epoxy (as in glue) to spray on the model. West Systems laminating epoxy resin is a different animal, as everyone knows, and was never mentioned until now. The response I gave was in regards to this given information. Reading back over his post, there is a lot of specific information which is missing which can have a direct bearing on what the recommendations left by others should have been. For example, the type of surface to be painted, whether over some other covering used to seal the wood(fabric/silkspan/glass cloth), or bare/sealed wood, etc., whether the fuel was to be gasoline/glow, etc. Not to mention obvious things like whether the plane was already heavy, how big the airplane is, etc.
Automotive paints are widely used and quite popular in painting R/C aircraft. Radio South R/C even sells it custom mixed. It's the PPG Concept urethane paint line. So what if a plasticizer has to be added? Just add it, no big deal. Admittedly, not everyone has the $$ for automotive paints, and they are more often seen on large, gasoline powered craft, pattern ships, or jets. I have used Imron and PPG paint myself on a few pattern aircraft with outstanding results. Again, paint choice depends on the specific application in mind.
My mention of HobbyPoxy was an "example". Of course I know it's been off the market for many years, but K&B has a new line of epoxy paints that are available. Maybe it was a bad example, but it is a well known one, available or not.
So, before this thread becomes a "urinating contest", I will say to you, "good luck" with your idea. It's your plane to do with whatever you wish. I wouldn't do it that way, but that's my own opinion. I wouldn't have used Krylon, either, not without testing it first on something besides my plane. Since Krylon labels don't say "for model aircraft use", that tells me to test first. That is just common sense.
How about reporting your results with the West resin back to us in about 6 months? If it works, maybe someone else could benefit from the experiment.

Rick