I honestly think a WR with good speed is a bigger need than anything on defense. Our D is fine? It's impossible to play dominant defense these days anyway, there's no point trying to re-create the 2000 Ravens or something.
A much more urgent concern to me is that we could not score points in Kansas City and we lack speed at WR to keep the safeties back. You're supposed to be able to score points in today's NFL, you're not supposed to have a dominant defense-- nobody does.