I've only played the following: RE1, RE2, RE3, RE:CVX, RE4, RE5, and REmake. I haven't played RE2 in over a decade but it was my favorite game of the series and is presumably still my favorite game. For the hell of it, I'll rank the games I've played.
RE2
RE4
RE:CVX = REmake
RE3
RE5
RE1
CVX's atmosphere really bodes well for me. I love the pacing and setting. As much as I love REmake, I get tired of the mansion much quicker than all of the other games, but the game is so well designed and visually superb that it's on equal footing with RE:CVX.
RE4 is amazing and is my most replayed Resident Evil game in the series. I've probably gone through RE4 at least a dozen or more times, at least double the amount of times I've completed RE2.
But RE2 is simply my favorite because I think it has the greatest pacing, the greatest characters, the greatest boss encounters, the most frightening encounters, and the best setting. Advancing from the police station to the sewers and to finally the lab is amazing.