Even Buffalo has Cook who DC's need to really worry about. Patriots don't have a receiver or te keeping DC's up at night. No true game changers. Receiver and te need to be upgraded.
I don't think they necessarily need a game changer. Not when you have a QB like Maye who makes guys into game changers with ball placement. But right now, they're having a ton of success passing against defenses not overly committing to the pass. Improvements at WR would help allow them to maintain that productivity even as defenses adjust. But the alternative route of the running game improving to the point defenses can't adjust to the pass works too.
IMO, what they need on offense over the next few years:
1) Diggs/Boutte have to maintain their level of play
2) Douglas or Williams need to develop into a consistently reliable WR3 at least. If they can't one needs to be acquired
3) Will Campbell needs to maintain or hopefully improve his level of play
4) Jared Wilson absolutely needs to improve or, if he can't, eventually be replaced
5) Bradbury should be upgraded
6) Onwenu needs to maintain his level of play or be adequately replaced if he's too expensive
7) High investment should be made at RT to replace/upgrade Moses as he ages
8) Stevenson needs to figure out the fumbling issues to the point he can be relied on because he is a very solid player and Henderson needs to solidify himself as a real compliment to him
9) Henry/Hooper play at TE needs to be retained or replaced if those guys age out
I don't think they need anything flashy there to be championship level on offense based on what Maye has shown and the level of coaching they seem to have. That's a long list but all pretty attainable/realistic IMO. I think their big risk is that Diggs and the TEs age out as the other player development/acquisitions take another year or two to sort out. You have to time it up right where those holes don't open up as guys develop into the other roles.
If the above happens, I think they'll be multiple and versatile enough on offense to beat anyone consistently no matter how you play it, even without a true gamechanger outside of Maye.