would think it would have to be a WR. Maybe a LB, maybe a safety. I don't expect any big names/big splashes though.
I would:
Sign Reif for RT
Sign Byrd at safety
resign Alexander
Sign Jared Cook at TE
Sign a medium range CB or two
Sign a medium range LB
Draft Davis at 1-10
Draft Mahomes (if there in rd 2, doubtful), or otherwise BPA on defense