Wife and I were a Judge team a few years ago in the PMT tourney held on the Croix. Range from Stillwater to Prescott, no live bait. 49 catch/photo/release, 1 killed. only 1 was kinni to Prescott, 4 w/in 3 miles of Afton, about 8 north to I-94 (4 over 49?) the rest from Hudson north. Yes, the Croix can be a productive fishery. Putting them in your boat is the challenging part.
Personal choices St Croix 7′ to 8′. 7 is good all around, but 8 gives more leverage to throw the heavy stuff and helps do better figure 8. Everybody has their own personal choice of lures, just ask around. Happy Hunting.