Seasons 4 thru 6 Are the Best
I think the seasons with Will Lorin as the head writer are the best. You had the cross-cutting, cutaways ("You Don't Have to Kill to Get Rich, But It Doesn't Hurt"), and titles of episodes broken up ("Didn't We Meet at a Murder?"), as well as interesting plots and weird camera angles. The Curtis Kenyon/Ken Pettus stuff under the Sweeney/Finnegan production team is good, but the episodes from seasons 4 thru 6 seem a cut above the ordinary.
Lorin also apparently wrote the very last episode of The Untouchables with Leonard Freeman executive-producing.
"He IS Redstone."