IPA Dry Hopping since there is Zero hop aroma

I tasted my IPA that I made last week and it is sitting at 1.020 with 7.5%alc and I just dry hopped with 2.5oz of Centennial and 2oz of Cascade which I just tossed on top as I don't have a hop sack. That aside let me tell you a couple of things about it.

I got about 50IBU's into this guy during the boil and was expecting about 1.068 OG but got a 1.075 due to a slower sparge, I need to change my grinding plate to a little coarser.

When I tasted it during the gravity check and dry hopping I thought that it was plenty bitter, though zero hop aroma even with 3 oz of Cascade at whirlpool. Should I have just saved that three ounces to dry hop with instead? It was also right at the verge of being thick (seeing as 1.020 is 5% sugar). I know that carbing will help to thin it out, but maybe I should have added some sugar into it to get the gravity down to more like 1.015.

Will the hop aroma come out in that pronounced IPA way with this much dry hopping for 10 gallons? Will I need to make up a little sack of hops that I throw into the keg?

EDIT: I just realized that I also mashed this higher than I wanted to around 158. That is why it is so freaking malty like! I will be able to hop this bastid plenty, so maybe I will add some more hops and just pray for Jesus to shine down on my beer.

Immediately a Hop Tea comes to mind. Maybe add some honey and get it down to something like HopSlam by Bells.