"A+". I thought it was outstanding and one of my favorite Trek premiere episodes of any of the series. If it can manage to maintain this level of quality it may be considered alongside other critically acclaimed dramas without the second class status scifi is often relegated to, the way nuBSG was treated like like a straight-up critically acclaimed drama without the scifi asterisk when it came out. It manages to have plenty of TNG nostalgia callbacks without going over-the-top, yet at the same time is unlike any Trek series that has come before, including TNG. It's unfair to dunk on Discovery since they're two completely different shows and this is still early going, but the qualitative difference between the two shows is night and day. And that's speaking as someone who enjoys Discovery in spite of its many flaws.
Surprisingly for being mostly set on Earth and starring a human lead, it probably packed more aliens (mostly Romulans) and "synths" in that first episode than most Trek episodes do, and visited more locations —even if most were terrestrial— than most Trek episodes as well, with fantastic production design, CGI, and location scouting making for some gorgeous glimpses of the early 25th century Earth and beyond.
Stewart hasn't missed a beat, and delivers an emotional, compelling performance as a Picard that has been beaten down by age, loss, loneliness, guilt over his own failures, a sense of betrayal by a Starfleet and Federation that has lost its way, and a malaise over a lack of direction in his life out of Starfleet and tending the Picard Vineyard, which the "call to adventure" the central mystery of the show represents shakes him out of, which is kicked off by one of those rousing Picard TNG speeches about morality and duty and how it was just as wrong for him to give up on Starfleet as it as for them to lose their way. It's one of two Picard speeches and three very emotional scenes, the others being Picard's conversation with Dahj and his interview with the Federation News reporter who was grilling him for his roll in relocating the Romulan diaspora post-Hobus (which is just referred to as "the supernova" here).
Speaking of the Romulans, in the best traditions of Trek, the show returns to commenting on timely modern issues from a futuristic perspective, dealing with refugee crises and how they affect governments, discrimination against and banning of the "other" (in this case synths and Romulans), and how our actions, well-intentioned or not (I suspect not in the case of Starfleet Command's larger motives with the synths, though not Bruce Maddox for sure and Dr. Jurati necessarily), can have dire consequences years or decades later, including mass terrorism like the synth attack on Utopia Planitia.
I also disagree with the characterization that this is "dark and gritty" Trek. While the Federation may have compromised some of its values in dealing with the Romulan refugee crisis by stopping the rescue mission after the Mars attack, that's nothing unusual for its responses in other times of crisis. In fact some of the best and most poignant stories revolved around Picard (or one of the other captains or crewmembers) acting as Starfleet's or the Federation's moral compass when they had let fear lead them astray, and this seems to be continuing that tradition. Plus, despite the heavy subject matter and action scenes, it's both literally and figuratively the least dark and gritty Trek I've seen in some time, at least during the premiere. And the show makes it obvious with Picard's rousing closing speech and rejuvenated rise from his couch with renewed vigor and purpose that it's going to be all about reclaiming those lost Federation values with Picard leading the way.
The action scenes were well-choreographed and exciting. No space battles in the first episode, just small scale ground based martial arts, blades, and beam weapons, but still distinctly Trek with baddies beaming in and out at will. Gone are the days of slow hand chops and two-legged flying kicks though. This is action movie level fight choreography.
She hasn't done much else before this because she's still very young, but if her acting in this episode is any indication, I suspect Isa Briones (Dahj + a dual role) is destined for a long career. She delivered some emotional scenes, and partnered well with Stewart. I hope this is a breakout role for her. I also liked Picard's two Romulan housemates.
My only "criticisms" would be that it was folly trying to make Brent Spiner look like TNG or even movie-era Data again without some Marvel face CGI or something, but that can't really be helped, and isn't a big deal if you just look at him with a little side-eye instead of straight into the abyss of the Uncanny Valley as it stares back into you with its beady yellow eyes. Some might complain that this was a bit of a setup episode with some exposition, which it was, but that's to be expected from a premiere, and it was never boring. Also, many of the main characters and some of the prominent guest actors from the trailers and promos don't show up in the first episode, so some might be disappointed by that, but they will arrive soon enough.
Overall, this is a very personal, character-driven show so far with a phaser and martial arts fight thrown in and eventually some space battles in future episodes. Hopefully it remains more about the exploration of the human condition and how we treat others with the **pew**pew** being used to supplement rather than dominate the narrative.