Last I check it is only day 4 of free agency. Yes, building through the draft is the main route to go, but it doesn't mean we are done in free agency.
The first few days are for the top tier players and the huge contracts. With that portion of FA coming to an end, teams will now start focusing on the second and third tier players which is part two of free agency. This part will last between now and the draft. We are not going to be handing out anymore 5+ year deals worth $20+ million, but we will be able to hand out smaller deals to some lesser known free agents. Don't think that we won't. Smiley likely won't be the last free agent offensive lineman added, and there will probably still be some movement to help out the secondary.
We won't be signing/trading for 8 players in one day, but you may see a few more names being signed over the next week or so.