I have used Terminal.app since 10.0, and have never felt like it needed replacing. What is lacking in Terminal that would improve my day to day by using a different app?
(I can't remember why I switched. It must have been 10 years ago now, maybe more, and I've stuck with iTerm2 ever since (even though it annoys me with a new beta update practically every time I launch it). It could have been nothing fancier than the vertical window split. But there was definitely something that persuaded me to change!)
EDIT: this did get me wondering, and I noticed two things it does have that it looks like Terminal still doesn't: configurable mouse selection word boundary chars, and implicit copy-to-clipboard on selection. As an inveterate mouse selector, I wonder if it was these. I might well actually have the word boundary chars still set to the default ("/-+\~_." is what I've got), but I do use the click-to-copy a lot.
Why don't you just use the stable releases?
I used Terminal for many years, too, but switched to iTerm2 a little over a year ago as I wanted to learn neovim.
- split pane support - profile switching (I have my colors change for different environments I ssh into). - tmux integration