Nothing.
I have several decades worth of previous edition material, Dragon Magazines, websites, YouTube videos, and books from Third Party producers at my fingertips that there is nothing left to need that I don't already have access to in some form or fashion and can't adapt and adopt into my game. I especially don't need anything that has to be catered to 5E specifically.
But the biggest thing about having all this stuff from years past is that I have to take a little bit of time to find it, read it, and see if I want to use it. I have to put the smallest modicum of work and effort actually into my game so they can be where I want them to be. But you know what? That's the way I think it should be. Working on my game is a requirement and an important part of the process of being a DM. And if some of the stuff WotC gives me in their 5E books is not what I like when I play D&D... then I will go through all my other game material to find stuff I do and just incorporate it in... rather than just sit on my hands miserably and complain that WotC isn't making it for me.
I have several decades worth of previous edition material, Dragon Magazines, websites, YouTube videos, and books from Third Party producers at my fingertips that there is nothing left to need that I don't already have access to in some form or fashion and can't adapt and adopt into my game. I especially don't need anything that has to be catered to 5E specifically.
But the biggest thing about having all this stuff from years past is that I have to take a little bit of time to find it, read it, and see if I want to use it. I have to put the smallest modicum of work and effort actually into my game so they can be where I want them to be. But you know what? That's the way I think it should be. Working on my game is a requirement and an important part of the process of being a DM. And if some of the stuff WotC gives me in their 5E books is not what I like when I play D&D... then I will go through all my other game material to find stuff I do and just incorporate it in... rather than just sit on my hands miserably and complain that WotC isn't making it for me.