The middle to the end of May time slot was what I used for several years.  All the observations are accurate, in fact some of my best smallie and walleye action have been in that time slot (although, as mentioned, walleye can be slow).  If you are thinking slam, you probably need to drag a lure Burke, Sunday and Agnes (if you are headed THAT way).  I've had no luck with lakers on Kawnipi.  But hope that the wind is at your back going up/down Agnes ... that is a long haul into the wind (even worse if its raining all day).  I've done very well with white jig heads and twister tail grub bodies.  I'd go with chartreuse for the second color if it were me.  Of course, hard baits (e.g., yozuri, walleye runners) work well too.  If you catch smallies on rock piles, you could also go with spinners.

Swimming (intentional or otherwise) isn't much fun this time of year.  I'd take a solar shower or heat water on the campfire for personal use ... even washing your hands in lake water can be numbing after a while.  Wet footing is also less comfortable.  Good rain gear is a must in this time slot (both for wind and rain).

Mid-May with a mid-week entry ... you probably will see few people.  But, you are likely to still be in the permit window by then. 

All-in-all, I like being in the woods as they are waking from the "winter nap."  Unless you pick an exceedingly busy spot, you hare very likely to the be first campsite site user of the year.

dd