I don't like floating plugs because they tend to be bulky. My travel tackle box is just a large fly box. Plus I do a lot of river fishing and they're not the best for flowing rivers. They are very effective lures however so a good idea.

I forgot to mention I also keep lots of bare hooks, spinners, wire leaders, split weights, and 2 lead weights for sinking the pickerel rig or night line. Floats can be improvised or carved from wood easily enough. Some spare jig bodies aren't a bad idea either. A good chomp from a pike will shred a rubber jig body no problem. I use both rubber and buck tails.