By my count we have 12 former first round picks: Goff, Gurley, Donald, Whitworth, Barron, Easley, Peters, Tavon, Talib, Suh, Brockers & Cooks. The closest other team I could find was Philly with 10 (11 after this draft if they don't trade down). I think the average is around 7.
We also have 11 players who have made a pro bowl (at least once): Donald, Suh, Goff, Gurley, Cooper, Whitworth, Peters, Talib, Hekker, Zeurline & Shields. I expect that number to be at least 13 when they announce the 2019 pro bowlers (Cooks, Brockers, Joyner, Saffold and Woods should be in the hunt).
If this team stays healthy, it has the chops to become legendary.