Quite enjoyable, although I agree with some other commenters that it wasn't the strongest premiere. I thought the green juice and whole Chapel/M'Benga plotline was particularly rough, though dealing with the PTSD could be interesting in the future. It just felt rather un-Star Trekky in an otherwise solid show.
I'm also slightly unsure about how far they are going in regards to Spocks journey. I did like that they had an in-universe fairly believable reason for it from last seasons episode with the Gorn. I like that the show has a consequence for Spock, and I certainly don't hate it but just a bit cautious and curious where it's heading.
Otherwise I thoroughly enjoyed the episode, even with so little of Pike. The other characters are very solid and I liked that they toned down some of the quips and such. Looking forward to the rest of the season.
Yeah I keep a fairly open mind about these new shows and whatever retconning they end up doing. I also really do enjoy Peck in the role, I think he's doing a great job.