Loved it. I even felt relatively embarassed for watching this a year late. There is a common complaint that the movie was to stuffed and boring, but I found it gave you exactly what you wanted. Two alphas squaring off in a city. The visuals are also amazing, and I like how there is no eased intro, it just jumps right in. I also loved king gidorah's reveal, he being one of my favorites.
The environmental scenery and new designs of the characters of also amazing; I especially liked Rodan and Mothra. Also, it mainly focused around the monsters/Titans. Not on the humans as much as the main attractions of the movie. also noticed the significant foreshadowing to Godzilla vs Kong.
But, there are also a few cons: the movie in a complete view was great, but there were some minor details that did bother me. The plot of the movie made sense, as well as the whole character arcs, but it still felt somewhat shallow. It still have you what you wanted, and that too on a very wide scale, just a few more tweaks here and there in the writing could have been done. The acting was also very good, in my opinion.
All in all, a great movie.