I honestly like Quake II even more than the original Quake. The gameplay is fast and fun, the weapons feel good and the levels. while a lot bigger, are designed well, feel good to traverse and there is a compass should you get lost. Haven't tried any of the DLC packs, but I did play Quake II 64 which is included, and that one is fantastic as well. If you like Quake, you will like Quake II as well!

For those who own Quake II and want to run the full original game with the RTX version, I'll share what I discovered for your convenience. You can find Quake II RTX on Steam here:
https://steamproxy.net/steamstore/app/1089130/Quake_II_RTX/

The steps are mostly managed in an official capacity by Quake II RTX:
Install this game (Quake II) via your Steam Library
Install the free Quake II RTX game from your Steam Library
Launch Quake II RTX
Indicate that you want to use the full version of Quake II when prompted (not shareware)
Select the install path to Quake II
Quake II RTX will then copy over all the game files from this full version of Quake II.

We're not done yet though! Quake II RTX will still lack the music from the original Quake II. Let's fix that!
Open both your Quake II and Quake II RTX Install directories
In Quake II: Navigate to the "rerelease" folder and then the "baseq2" subfolder
In Quake II RTX: Navigate to the "baseq2" subfolder
Copy the "music" folder from Quake II to the "baseq2" folder in Quake II RTX
That's it!

Now you can play the full Quake II game with RTX and Music. If you don't intend to play Quake II without RTX, you can now uninstall Quake II as all necessary files now exist within your Quake II RTX install. Enjoy!

Note in my personal opinion, the changed lighting really modifies the vibe of many of the environments, in general feeling a bit more washed out, sometimes much darker, sometimes much brighter. But it never feels flat like the original can sometimes be. You also miss the split-screen features and additional campaigns, so there's good reasons to enjoy both versions. Naively / without nostalgia, I think the RTX visuals will be more appealing to newcomers, or those without a lot invested in the original version.
That said, I really do think this remaster holds up really well and has a ton of great features to warrant playing without RTX. The animations look better and the lighting is just more artfully handled.

spent eleven hours installing windows 98 so I could play this game properly