IDK. Pilsner with 5% Munich I vs. 5% Munich II shows more noticeable differences in flavor and aroma than in color, IME.
But then, personally, I don't like going either route. I've learned that I prefer to just use a base malt kilned to just north of 2L, to get the desired extra melanoidins. The lightest (simplest) melanoidins being the subtlest -- so you need base-malt quantities to make an impact -- but also the most pleasant; the darker (more complex) the melanoidins, tending toward N-heterocyclic products, the less stable and desirable.
A bit of a digression, but it brings me back to the OP: I find that base malt makes an enormous difference/impact, and attention to it is more rewarding than trying to correct for deficiencies there by adding specialty malts. In short, I feel for poor Richard and his wallet.
But I'm inclined to think that the Admiral malt was the key.
That said, it might be worth your effort, Richard, to try some other base malts, available online or otherwise, which may be more affordable but still a level above the usual commodity brewer's malts. There's a malt revolution going on, not just with new craft producers, but the old companies are offering new, more craft focused lines also.