Originally Posted by terrapinj
isn't .5oz pretty small for 15min and 5min additions?
I agree. Try moving those 60min additions down to your 15 and 5 so you have (at least) 1.25oz at each addition. Then add a bittering hop like Warrior, Chinook, or CTZ. It can add up in price, but you just won't make an IPA with that hoppiness you're looking for without adding more hops.
I like the use of Willamette in an IPA though! I did that for an IPA once and it was one of the best beers I've made.