Game had a lot of potential, but the engine was dated and Romero's PR campaign backfired on him. In Daikatana, one can see that Romero wanted to take the FPS to new heights gameplay wise (the rpg elements,the skyscraper level, etc...). Carmack, on the other hand, wanted to make engines. Some believe Carmack won, but I believe gaming lost. After Romero left, ID games were lacking in the gameplay and imagination department. I would have loved to see where ID games would have gone if they stayed together.
Romero was and is a vital part of game development.