I experimented with APAs and AIPAs several years ago, investigating the appropriate grist composition when you have high hop flavor and aroma. My goal was to increase the complexity of malt flavors, but not really move the wort color from the style guideline ranges.
I produced great tasting beers with nice malt complexity underlying the bittering, flavor and aroma of the American hops. But, the complexity of the malt flavor actually interferred with the hop flavor and aroma and clashed. While they were within style, it was apparent to me that when dealing with the level of hopping in a good APA or AIPA, the malt flavor needed to be cleaner and nearer to a single-dimensional malt flavor.
I now have been more typically using a grist composed of mostly pale 2-row with a single crystal malt. I see that there has been a popularization of Tasty's APA and it uses pale and pils with some crystal. Seems to be in line with my thoughts, but even lighter malt flavor. I don't see why using either a single pale malt or a simple combination of base malts couldn't produce a good version of these styles as long as the brewer keeps the crystal addition fairly simple.