Inspired by the linked XKCD. Using 60% instead of 50% because that's an easy filter to apply on rottentomatoes.
I'll go first: I think "Sherlock Holmes: A game of Shadows" was awesome, from the plot to the characters ,and especially how they used screen-play to highlight how Sherlocks head works in these absurd ways.
A lot of critique I saw for it was squarely aimed at Keanu Reeves. Early 00s popular opinion was he doesn't act and plays the same character in every movie, with monotone voice and muted expressions. Quality cast with lots of talent, special effects for the time that were at least on par with what was popular for the years prior to it, and a story that keeps twisting and turning it felt like the lore was being made up as it went, which was confusing to more casual audiences who maybe were hoping for a Matrix spin off given Keuna was starring. And of course it being attacked by the religious conservative crowd for using Christian themes and twisting them to be satanic, completely missing the point of the movie.
On the other hand, fans of the comics and character of Constantine were equally upset that Keanu was starring, and while he managed to be mouthy and snarky, it wasn't to the level they were hoping for (this shouldn't have been a surprise given that Spider-Man in the comics is also known for his mouth while the live adaption at the time had him being fairly quiet.) So they blasted the movie for just being a rip off or Hollywood water downed imitation for what was otherwise a very adult and out there character who has more tricks up his sleeve than batman.
Personally, thought the movie was great and loved it, I can understand the critisms but the fact that the movie got made at all was a small miracle and that it turned out as well as it did with the climax being a rather memorable scene with John giving Lucifer the finger.
That's fair criticism towards Keanu I suppose but I thought it fit his character. Plus the supporting cast was great, as you noted, so I didn't notice as much personally.
I never read the comics so I didn't have that context. I can appreciate that viewpoint though. I would probably prefer a character that's more similar to the comics if I had read them.
Ultimately I agree with you. All the twists and turns with a great ending made for a very enjoyable movie.
If you like the movie I recommend picking up the novelization. It's a slightly different version of the script in a couple places but it does an amazing job of filling in a lot of details and how the magic works, and some stuff that was cut from the movie (the half breed demon Constantine is in a relationship with, etc).