I mostly use the default terminal emulator in the desktop environment I use, currently this is the gnome terminal.
What are the main reasons one want to use another terminal emulator? IMHO if I can reszie the window and the font and font size is good or configurable it is fine..
Some offer specific features like tabs/splits, or Quake-like drop-down. Others are just focusing on being fast to launch, or have performant rendering. Having barely any features can be a desirable feature in itself, depending on who you ask lol