With the 6 teams on bye week, one of my starting receivers is Julio Jones. My bench is made up of my usual starters (on bye week) and Chase Edmonds. Do I drop Edmonds and pick up Mecole Hardman in case Julio Jones does not play? Drop Julio? Drop my Defense or Kicker for the week to pick up a receiver or trust that Julio will play? The league is a rotisserie league (not HTH).
Your last question is your answer. If you can drop your K or DST, that is always your best option. You may end up losing them to somebody else, but 90% of the time you can pick up somebody as good or better later.