I meant I find AutoMKV's interface a complicated mess.
There's no individual settings. It's all mashed together. If I were to make an interface, it would probably be just for x264 only and provide simple, easy, organized choices.
Yeah I have a feeling MeGUI doesn't try to oversimplify the process as much by bunching settings together like that, which may in someways be actually more complex. It's probably more popular still with the more script savvy users, but from from I've read you do have to know more to use it vs AutoMKV.
As popular as x264 has been and for such a long time, it's kind of surprising there isn't more GUIs out there to configure it, and none I know of with a built in viewer like VirtualDub. Then again VDub is more of a minimalist editor than mere GUI.