Mixing of Hops

Seeing as most everyone here is much more knowledgable with brewing than myself, I thought I would get people's advice on mixing hops.

I had originally intended on brewing my latest batch of dark ale using 1.5 oz Hallertau for the main hops and using 0.5 oz Fuggles as a finishing hops. But thanks to my homebrew supplier, one of my packages of Hallertau hop plugs was poorly pagaged and went bad, despite the fact that I stored them in the fridge. I was left with using 1 oz of Hallertau and 0.5 oz of Fuggles as the main hops and 0.5 oz of Cascade for finishing hops.

Edit: I guess I should also add that I am using SafBrew T-58 Ale yeast, which is supposed to give a more spicy flavor. I also intend on using 2 oz of American Oak chips during the last 10 days, which are currently marinating in corvaisier .

I know that the scents between Cascade and the other two are quite contrasting, but I think it could make for an interesting concoction. I guess my question is this: would mixing such contrasting hops be a disaster in the making? Or has anyone had success with such things? Thanks in advance.

I think the Cascades would overwhelm the brew. You would probably be better off using just the Hallertau and Fuggles. It would be slightly less bitter, but not by much. Hallertau is only 3-5%.