The "pale" ale I'm drinking at this very moment was--I believe--1/3 Pale malt (probably Belgian), 1/3 Vienna, and 1/3 Munich. I only assisted in its brewing, so am not entirely sure of the grainbill. The grainbill was somewhat modeled after the German IPA that I did with roughly the same ingredients.
Crystal malts are perfect for extract brewing. But, you're right, now that you're doing all-grain you can use things like Munich, Vienna, other pale malts, or various specialties along with tailoring your mash to create the same residual sweetness as you were getting from your crystal malts, but possibly with greater flavor complexity.
I've also brewed some highly hopped beers with up to 25% Munich, which I received good compliments on. One also had a lb of wild rice. I personally find that the darker malts (MO to Vienna to Munich) give a really nice malt backbone that compliment heaps of hops very well. But it can become quite a heavy beer.
I think the "American pale ale" tradition has always been to use a neutral yeast with a neutral grain bill and allow the hops to dominate the flavor profile (i.e. SNPA). While I think there is a time and place for these beers, there is also room for new interpretation (see Surly Bender or some of the recent IPA's from Belgium).
The crux becomes finding out what to call these beers...they're really not that pale. I saw a recipe in Zymurgy a couple months ago for an Imperial Amber, basically an IPA that was amber instead of the typical pale.
