I absolutely get where your coming from and can't fault you for wishing that. Heck who wouldn't like a high flying offense that attacks opposing defenses weakness. I hate to use this example but the pats have been a model of that. If their opponent has good CB they throw to the TEs all day, if the opponent is has good linebackers they'll pass outside or screens, if the opponent has an elite secondary theyl run all over you. Unfortunately, that model is almost impossible to replicate.
the thing with a high flying offense is that you need an elite QB, RB, LT, and WR. That's half your cap space right there and if any of the 4 gets hurt then your offense becomes one dimensional and crippled so it's a risky proposition to say the least. Elite defensive players are a bit cheaper cap wise and more consistent. Usually an elite D can take a few injuries and still be top 10. Don't look at our D because we had no depths what so ever at CB but in general that's why Defense is more reliable.
just look at the past SB winners, they all have too 10 defenses and the high flying offenses that force their D to compensate (cap wise) usually win a lot of regular season games then fail in the playoffs because they face good offenses and elite defenses.