Probably among the weaker efforts in the Marvel MCU, it's still a cut above any most non-MCU superhero movies (note: have not seen
Logan yet.).
Dr. Strange gets points for trying to stay true to the original comic book by angling for a hippie/spiritual/psychedelic head trip vibe and it succeeds to some extent. One critique is in tone. It was clearly a struggle to find the right balance between the sincere, reverent tone that characterizes most spiritual journey-type plots with the wisecracking irony so essential to the charm of the MCU. Dr. Strange is played by
Frumious Bandersnatch Benedict Cumberbatch employing an American accent which, given his ubiquity in his normal voice, is quite dissonant. Perhaps this is part of the reason that snappy dialogue isn't all that effective here: there is not much of it and what there is is given solely to Cumberbatch, everyone else gets standard sci-fi/action movie words and roles. It's a moment of happy relief when the post credits tag brings Thor into the mix, if only for a few seconds.
Overall I'd guess it was a struggle to make Dr. Strange as formulated carry a film on his own. He needs a foil like Sherlock needs his John. Unfortunately, Martin Freeman already has another role in the MCU. To live on, Strange needs a partner to bring out the best in Cumberbatch, and a villain and supporting cast who are more than dire drones.
This review turned more negative than I had hoped. I don't want to scare you off of
Dr. Strange. It's a solid entry in the MCU and a good couple of hours of entertainment but don't look for anything too special. It's mostly just a plot advancer for
Infinity War.