Thanks guys. Simple is what I was going for, easier to tweak later without too many variables, and i have a pound of centennial hops.
Thanks Yooper, I'll give it a try. I really like more flavor and aroma hops and less bitterness, but was unsure how to hop it without underdoing the bitterness.
You want a nice firm bitterness, but I think 1.5 ounces (FWH) is fine. I didn't calculate the IBUs, but I doubt they dropped significantly by reducing the addition a tad.
This recipe isn't that much different than the Stone Ruination clone, except I used magnum for bittering and not quite as many late hops. https://www.homebrewtalk.com/f69/stone-ruination-clone-155771/
Centennial alone makes for a great hop profile. At what temperature are you planning on mashing? IMO you want IIPA to finish somewhat dry, a bit lower than 1.019 like your recipe is predicting. With wlp001 and a mash temp in the low 150's that shouldn't be a problem, just be sure to account for the increase in abv if that's of concern to you.
I'm planning on mashing at 150. I was actually hoping for it to be dry, but I don't think Beercalculus accounts for mash temps when it calculates attenuation. The FG prediction doesn't change when you change the mash temp on the process page.