Doom is still a great game even after all this time. And here are some very useful tips to get the best out of this amazing game.
Doom HD sprites project.
https://forum.zdoom.org/viewtopic.php?t=67765 This project brings HD sprites to classic Doom. This would make the game look amazing.
Doom HD textures.
https://www.moddb.com/mods/doom-hd1 HD textures to improve the look of the game when running Gzdoom.
Hearing the Doom sounds is still amazing even after all this time. Here is a mod that brings higher-quality sounds to Gzdoom.
https://www.doomworld.com/forum/topic/110822-doom-sound-bulb-hd-sounds-that-stay-true-to-the-original/ Doom Sound Bulb – HD sounds that stay true to the original!