re: Do you worry that a revamped, higher octane offense might make defense worse?

No. Elite defense will consistently makes stops, sacks, and turnovers when needed.
will high scoring offenses they'll occassionally give up 24/31 or so ect, but if the offense is putting up points who cares

in modern football you cant just have a smothering defense anymore. there will be a game or two a year where you'll need to score 42 plus to win.