The St Croix between Hiway 48 and Hiway 70 has some nice camping and fishing spots as well as scenary.  I believe there is now a parking lot at the point where hwy 48/77 access is otherwise go into St Croix State Park (parking permit required) and put in at the Little Yellow Banks landing.  Aside from the Kettle at 48 to the St Croix at 70, the St Croix at 48 to 70 is my second best prefered river route in the state

Virtually all of the DNR and USFS campsites along the route are very nice.  Fishing is typically good around a number of the islands on the route.  The rapids between the 110.5 and 105 mile mark on the map are fun to run and should present no problems (some areas are at the high end of class II in the spring when the levels are high but fall is fine).  

If you have water containers, they can be filled at the spots along the way where water is showing as being available on the maps, however the DNR does begin winterizing some of the spots right after Labor Day so bring a filter for or boil the river water if you use it.

Hope this helps

WR