Another addition to the ZDoom family is Harmony, a game 8 years in the making and while it shows, there are fogies like me who actually play these. The creatures in the game are actually scanned clay models, a retro idea for sure but it adds to the overall flavor of the title.
If you want addition old skewl goodness, you could try 3D Realms download page. You can dial the way back machine a few more notches to the no graphics at all, free downloads of text only games such as Kroz, Beyond the Titanic and Supernova.