Too large of a reel makes your combo butt heavy. Too light makes it tip heavy. This affects your casting & rod tip sensitivity in feeling a fish strike. It also affects your comfort, because you have to compensate for the unbalanced rod & reel. The best way to judge, is to physically put together your combo and feel it for yourself. Take a rod or reel that you own, and try them out in the store where you plan to buy the companion reel or rod.