Good points, I am curious to see if DDG's career follows the path of the likes of our own Edwin, Buffon, Cech and Seaman in they arguably became better keepers in their mid 30s than when they were younger. Then again one criticism I have of DDG is he doesn't seem like a commanding presence barking orders and keeping the defence on its toes.
Not sure I agree on that set being better, but it does touch on the one thing I always wonder about De Gea. You typically have two extremes with
great keepers: T1) tall, large frame, great positioning, gets better with age (experience = anticipation/reading/positioning/commanding), T2) smaller, nippy, rely to a great extent on their athleticism so tend to go to shit once they hit ~30 (Goram, Barthez, Casillas, Bravo*).
Of course in many cases there's a mix, e.g. Peter Schmeichel, who could still pull off incredible flying saves well into his 30s (these caught the eye, sure, but it was his T1 traits that made him so dependable). My concern with De Gea is whether he is a bad mix, not sure the getting better with age bit in brackets applies (at least not his strongest suit) and he relies a lot on his reflexes, which are bound to suffer. He should be progressing and getting better at those things that are not affected by age but, instead, he persists on relying on strengths which don't age well.
*Wouldn't exactly call him great, but helps see the pattern of form falling off a cliff