Starting with Tmux was quite eye-opening to me for exactly this reason. The power of composable tools is hard to exaggerate.
Can you give some examples of what you're able to do or what exactly you mean by composing in this context? I've used tmux a bit but just to split windows and restore sessions...
Feel like I'm stuck at this point myself. Sort of plateau'd my tmux at "persistence / tab manager"
Vim + Tmux + SSH is probably the most common/generic example. This stack allows me to, for example, work from my iPad Pro.