I like the grain bill. I'd probably cut the crystal a bit to 5-7%, but otherwise I'd leave it.
I'd totally change the hopping. Any hops added before 30 minutes from the end of the boil are bittering additions, so you've got three bittering additions, but nothing (except liberty) for flavor hops and none at all for aroma additions. Liberty hops are great- nice and "clean" and pefect for lagers and other super clean beers. But it doesn't fit at all with an American IPA.
I'd totally redo the hopping to this:
1.00 oz Centennial [10.00 %] (60 min) (or to get you to 40 IBUs)
1.00 oz Cascade [5.50 %] 15 min
1.00 oz Amarillo Gold [8.50 %] 5 min
1.00 oz cascade or amarillo (or 1/2 each) at flame out
1 ounce BOTH cascade and amarillo dryhopping
American IPAs are all about hops. A nice solid grainbill for the malt backbone, and then hopping at 15, 10, 5, 0 and dryhopping, all with American hops will give a great flavor.