I agree that Star Trek has always been at its best when it's moved forward and not been stuck in the past.
Not so sure I agree with that. Trek has been about nostalgia ever since TMP came out (assuming one considers TAS more of a contemporary extension of TOS) and its biggest big-movie success was a continuation of a TOS episode shot some 15 or so years prior.
The movie franchise then went on to milk the TOS cast for six movies, most of them successful, despite the aging cast.
I find bringing Patrick Stewart back totally consistent with the above track-record.