i can't believe no one has replied to this yet. i'd think an inquiry like that would have had some people here just rattling off lists.
i can't help you much. i don't fish. my only trip to the uintas was last year. my brother and i hiked kings peak from the swift creek trail head. we went up swift creek, over bluebell pass, and then took the highline trail over to the pass below kings peak. kings peak is an easy walk up a rock field. on the way back we took the trail that follows yellowstone creek all the way to the trail head for a semi loop. this was probably a little over forty miles. we did it in two nights.
if i were taking a group of scouts, i would think that including kings peak would be a cool thing to do. it's possible to spend more time around the timothy lakes, up the swift creek trail, than my brother and i did, and i think that seeing the highline trail at all is pretty cool. bluebell pass was nice, and i'm glad we went over it. the trail is light in some places here, and we enjoyed following cairns every now and then. the scenery along yellowstone was not quite so interesting as along swift creek. a lot of beaver dams along swift creek. you could also do a very similar loop from the north side to kings peak, using the highline to connect two trail that return to the same head.