I don't see blobs mentioned, worthwhile to have some. While
@PeteM mentions pumpkinheads*, how about plain damselfly nymphs in a few muted colors (colours - BC, eh), last year Keith slayed 'em casting skinny, sparsely dressed tan coloured damselfly nymphs towards shore, close to shore, while Herb and I tried to figure out why our mayfly emergers were being mostly ignored. Sometimes it's the streamer that gets the bite. Bring the kitchen sink.
* Thread drift: A guide we've used a few times in the Thompson Nicola area told us he was fishing Tunkwa/Leighton and catching some fish. He caught a big, fat ripe hen and "milked the doe" (his term for squeezing roe from the ripe hen). He noticed that damselfly nymphs were eating the eggs so he came up with the idea for the pumpkin head.
Good luck, we'll be up there May 29th through June 6th.