We too have a lake like that (and I have to mention that Henry's Lake is a shallow lake with a lot of veg. No bass, bluegill, just enormous Cutts, and Rainbows)
Anyway the lake we have here is stocked with Bluegill, and bass and recently some bucket biologist introduced crappie. I have found in the colder months that the rainbow would be more towards the surface (warmer). I use a black and purple woolley or Gartside Softhackle and have good luck with them. When it warms up I switch to Brown/Olive softhackles. I use an Intermediate line and strip slowly with a jerk, jerk added.