Crystal 120L is very "raisiny" and toffee-like. I'd probably leave that out, and you've already got over 5% crystal malt with the crystal 80L. My preference for crystal malt in IPAs no higher than 60L, but I do like a mix of 20L and 60L, depending on the recipe. Keep it under 7% or so, though.
I'd change the hopping a little, just to make it nice and hoppy. I'd move the 30 minute addition to either bittering, if you need more IBUs, or to the end for flavor.
I'd probably change up the recipe more like this:
18.00 lbs 2-Row Pale Ale Malt
4.00 lbs Vienna Malt
1.00 lbs crystal 20L
.75 lb crystal 60L
2.00 Chinook 60 mins
2.00 oz Centennial 15
2.00 oz Williamette 10 mins
2.00 ozs 0.00 Williamette 0 mins
2.00 ozs 0.00 Cascade 0 mins
Dryhop 5 days with the cascade/willamette combo (at least 1 ounce of each).