Agreeing with you up until this point.
The Ravens had a very good rate at avoiding 3-and-outs. Of their 192 drives, only 35 ended in a 3-and-out, which is an 18.23% rate and good for 6th best in the league (LINK). That's in front of teams like the Packers, Cowboys, Steelers, and even the Patriots who were bottom 6.
Also, the Ravens had a positive TOP on the year and were above-average (12th overall) for the league (LINK). The defense blowing leads had less to do with the offense and was more on their own failings. Losing Jimmy Smith really seemed to tank that unit and Pees could not adjust adequately - didn't help that some prolific offense came through, too.