It really depends on your tolerance for long drives. Corner Brook to St. John’s is about seven hour plus stops. Being originally from there I am biased to say it is well worth it, but not sure you want to spend two full days driving. You should certainly do the Western Brook Pond boat tour in Gros Morne.
Yeah, I guess since we'll have a week or so, spending two days of it driving all day might not be the best use (unless we fly into YYT and out of YDF with a one-way car rental). Thanks for the Western Brook Pond boat tour suggestion. It looks amazing.