I was going to wait on comment on this after the season but I'll do it now. I think there are multiple reasons why offenses (and the passing game) are rolling so hot right now. As noted, you need to be careful when making adjustments because its not a single thing that is the variable.
These are my observations with my MFN-1 Carolina team:
-I have two stud DE's (high 90's) that generate pressure (I think) but have the lowest sack total of my long career in MFN. Not sure why that is but I'd like to see QB pressures added to help me understand what is going on.
-OL seem to hold their pass blocks way too long vs. top tier pass rushers. Again, I have 2nd tier tackles high 70's mostly stalemating my stud DE's more often than not.
-I lost my long time top shelf CB last year but I carried two fast stud corners for awhile that were in the 90's as well/ They typical where close to the top in INT's but still had tons of passes completed on them. Even against mid-tier WR's they would still allow around a 40% completion rate. A mid 90's CD should dominate a mid 70's WR more than what is going on right now.
-More coverage should be given when there are two or more players on the WR. Its not clear how much harder it is to complete a pass against double coverage than single. Having a safety coming that can close on a route along with a CB should be a difficult pass to complete. I don't show many passes broken up by my safeties.
-This goes both ways. I have one stud WR who puts up great games but the next tier down for me are almost as good in terms of production if I put them in the WR1 spot.
-I don't think the CB quality is the whole issue, it is some, but my CB's are fast and can cover and they cant dominate a lower tier player. Speed only shows up on the deep routes and for pursuit after a blown tackle.