I guided for 3 years near Ear Falls and all I used was 50lb power pro with a titanium leader. I caught more pike in a summer then most people do a in a life time, 50lb is plenty strong, I casted large baits and no break offs landed many pike over 40 inchs. The heavier the line you go the harder it will be to cast. For spininng reels you should run the same diameter line you would in mono or the line will not sit on the spool well. 30 lb power pro on a spinning reel would be fine with a good leader. Make sure you using a rod that can handle that heavy of line also, if the rod is to light, heavy line alone will not get a big fish out of the weeds.