I was myself a fairly dedicated emacs user and what I like so much about the Lively UI is that you a) get all the programmability and customizability that you h

I was myself a fairly dedicated emacs user and what I like so much about the Lively UI is that you a) get all the programmability and customizability that you have e.g. with elisp (all the stuff on the screen can be programmed, keybindings, windows, everything down to the characters in texts) while b) get a user interface that is way more powerful than simple text. It's easy to embed images and interactive objects into normal texts allowing things to be more interactive to use. It's easy to plot and visualize data (interactively, not just a static screen), e.g. see the plotly morph in the partsbin. There is a sketch morph in the PartsBin as well, allowing you to sketch and take handwritten notes, I use this in combination with Astropad. Etc. All that stuff makes the environment much more convenient to use for general content creation, not just programming.