Thanks for the input, darefsky.
Yeah, I assure you that's not a case of paint being too thick. There are definitely spots on the model that have a lack of detail and depth for some reason.
An example would be the "mesh" texture on the model's inner thigh; it's so subtle that when even the thinnest coat of paint is applied (after primed), it almost creates a smooth surface, so wash basically doesn't even flow into the recesses.
That said though, Infinity models great to improve my skills upon.
I'm sure that once I get my copy of Angel Giraldez's Masterclass book, I'll be cranking out Golden Demons in no time.