Lombardi, Paul Brown and Bill Belichick are all on the Mount Rushmore of NFL coaches.
Of the remaining coaches, I would probably give Walsh the nod. His iteration of the new "West Coast Offense" was hugely influential. 3 SB titles and he was really the architect of the 49ers 15 year run of 5 titles. Joe Gibbs is in the conversation with the Nolls, Shulas, Landrys and Halas, 4 SB appearances, 3 SB titles with 3 different QBs.
Belichick could probably get in the NFL HOF just for legendary run as DC for the Giants and later the Pats. He was the architect of a defense that frequently frustrated the 49ers. He was also the genius of the scheme to shut down the Buffalo Bills, which itself is in the NFL HOF. Soon as he joined the pats as Assistant HC, they immediately made it to the SB. 9 SB appearances as HC, 6 rings, 3 SB appearances as DC 2 rings. He has 8 rings!
No way you can put Walsh, Noll or Shula ahead of him. There may be an argument for Brown or Lombardi, but I don't think any hold much water.
It has suddenly become hip to knock BB and as much credit as Brady deserves, Brady does not become the player he is without the greatest strategic mind the sport has ever seen.