There are different types of flavors from bittering like grapefruit bitter or sharp/tart citrusy bitter alot of time piney bitter or herbal/earthy etc...I think it gets blurred out from people describing hop flavor only mainly with mid-late additons.Yes those are prominant hop flavor additons but you also get a type of flavor bittering also-I believe. In how it finishes.
Yours wont be all centennial but I think centennial has a citrusy type bittering. Galena is a good bittering hop,Midwest describes it as fruity candy like,slight citrusy and herbal but slighlty rough. I think galena is fairly close to Nugget also I gotstronger herbal/earthy character after they started to fade and as my beer aged with them. But you are talking about just bittering here. Should pair good with centennial though. Shouldnt really make a significant difference at all though just to get your Ibu's up a little.
