I have watched a few VODs of a current player doing an A16.4 play though.If you get bored of 2.0 before 3.0 gets here, give 16.4 a try (assuming PC ofc). It might not be that great to go back, but it's basically a different game. I'm suggesting 16 and not 17 for the zed AI changes, iirc they came in in 17 and the first patch with it was .. obnoxious. It may have been toned down by end of 17, but if you want to see the "classic" vibe, 16 or earlier.
I thoroughly enjoyed the sandbox feel without the Trader Quest focus of the current versions. The nostalgia for this was real and I often play the current version this way. I did like the darker look and the subdued color palette. I also liked looting zombies.
The weapon part and vehicle part system seemed promising. I liked the simple but slightly extra complexity for immersion. It was also nice because zombies also seemed to hit like a freight train. That will appeal to some, and also not appeal to some, depending on their approach and play style.
I get the satisfaction of seeing the dripped accomplishment feedback that "Action Skill increased by 1". But I did not feel any nostalgia for the LBD system. It was overly large and bloated. At one point the player stopped to spend 47 skill points (or something). Hence, it did not seem to add any real "fun" to the gameplay experience. The wellness system was extremly punishing and the depleting wellness death spiral loop was real.
The Zombie AI was unexpectedly poor. When not close enough to the player they just ran in circles. The zombies never seemed to target a player, only random blocks. I can see why TFPs jury rigged the zombie AI to "see" doors and hatches with reduced HP, becasue without that "fix" combat was extremely tedious, enlessly looking for angles or trying to hit zombies as they passed an opening.
The intervening Alphas have addressed most of the jank, the hit boxes, and a lot of the other niggling stuff.