We typically trip in May or June but our last 2 trips have been in August and there was a slight adjustment we had to make with finding walleye.  As the water warms, walleye will move deeper (20-30') off the same structure during the day and can be relatively inactive.  As the sun sets they will start to move shallower for food and your best fishing will come during these later day hours.  Walleye and bass will share the same habitat so if your on bass, you are probably on walleye as well; the bass are just more aggressive.  I really believe that mid-lake structure is the best structure because they have immediate access to deep and shallow water and with the wind pounding those mid lake humps and reefs all day, the baitfish are plentiful.  Rarely do I go heavier than 1/8oz jig usually tipped with 4" Gulp shad or cisco.  We have had inconsistent success with the Gulp leech.  IMO it has poor action in the water.

Lastly, I'm a bit cynical with trip reports and stories that give an impression that "walleye were everywhere."  They're not.  While they are plentiful I consider a successful walleye day with 4-5 fish.  Like you, fishing is our priority and we spend no less than 12 hours in the boat per day weather/wind permitting and in 20 years of Quetico camping, I can count on one hand the days when catching walleye was ridiculous.  Those days were just good luck and right place / right time.  But, if you see a storm brewing - get in your boat and get to a shoreline that will receive the wind and soak a minnow.   ;)