Low-profile reel capacities are more than adequate when running lines such as 12-15LB UG and up to 30lb braided lines. My arsenal seems to include 200 series Curados, Revo STX and the Daiwa Zillionaire and the Viento.

I honestly can't find a valid reason to use a larger reel for the most part when fishing Washington rivers. Spoons, spinners, drift fishing, float fishing really doesn't require a lot of line.....

Might bump up the reel size a notch for kings so there's plenty of capacity for heavier monos and braids. Consider a Curado 300, or Revo 50 if you really want to go big, or fish bigger water (Columbia, etc). I like the Toro 50 with 50-65 braid on it for things like divers, plugs, herring, fish-flash type crap, etc. Plenty of capacity for that.