Modifying Two Hearted Ale Recipe - Need Suggestions

I am about to transfer NB's "Three Hearted Ale" into secondary. The recipe calls for 1 oz. of Centennial dry hops to be added after a week of secondary.

I have about 4 extra oz. of Centennial hops in my fridge. I like my beers bold and bitter; I'm considering adding more hops for perhaps the entire secondary. This is only my 2nd brew and I haven't modified a kit recipe yet, so I don't want to screw anything up.

Any suggestions? Maybe grab a different type of hops to add some other flavors to the beer?

Adding more dry hops certainly sounds like a good idea, but it won't add any more bitterness. Dry hops add aromatics, you have to boil hops to extract bitterness. More Centennial would be welcome, but if you wanted to mix it up some Amarillo, Simcoe, Chinook, Columbus, or Cascade would all work as well.

Keg or bottle?

I've been dry hopping w/ 2oz of centennial in stainless tea balls in the keg throughout service. Tis hoppy and nice.

This will be bottled. Thank you both for the info. I think I will double up on the Centennial and put some in early and some in late.