I agree with the OP. Patriots have 4 starting Offensive skills players that are 30+ (Brady, Edelman, Hogan, Gronkowski). Actually Gronkowski is 29 but needs a walker.
As long as Belichek holds onto that core as starters, IMO they will slow down/injured even more and get passed very soon by both the Bills and the Jets.
Let's hope Belichek stands pat with that crew during the offseason. If he does, next year could be 3 teams at 9-7 with the Jets & Bills fighting it out thereafter for quite awhile.