Do you know what your water profile looks like? If your water is very soft you may consider adding some gypsum to help accentuate the hop flavors. Also, are you pitching enough healthy, clean fermenting yeast like WY1056, US-05, etc.? Are your fermentation temps under control? All of these factors may affect your hop flavors.
Also, as bob3000 said, you won't get much from .5oz of cascade at just 30 & 15. I'd back off the Chinook for bittering (depending on the aa%, of course) to .5 to .75oz and up the cascades to an oz each at 15, 5 and flameout. Then dryhop with 2oz. after fermentation is complete.
Also, I'd do 1/2 the extract at the beginning of the boil and 1/2 towards the end.