Rosies would not be an advantage for pike, trout maybe, they are typically too small. Smelt work fine, if you buy them frozen thaw them out overnight in the refrigerator. However what I have found to work even better than smelt were sardines. Fresh, if you can get them, but frozen are just as good. Don’t use canned or salted, etc. Only place that sells them in my area is an Asian market. Average size of a sardine is 6-8” so it attracts large pike and musky. When you drop your bait in the water you will actually see oil in the hole from the fish.