For me the killer feature is truecolor support. 256 color is rather limiting, and with truecolor you can also use gui syntax highlighting color schemes. My actual shell runs in a neovim :term, with neovim running in alacritty, so I dont care about fancy terminal features other than rendering and colors.

Why inside neovim? What's the benefit?

I used to use tmux but the vim commands were incomplete, and even with vim integration plugins, the separate buffers and separate window splitting gets in the way. I wanted to just use the same pane splitting and navigate and use the terminal output the same way I use my text in vim. Neovims term was good for the purpose, supported all the term stuff I needed, and I could open straight into it unlike in vim, so I switched to neovim. I've had no issues with terminal stuff since so I've no desire to switch. I also prefer the scrollback history in nvim over built in terminal emulator scrollbacks that I've used.

Many terminals lack ligatures. Once I started using a monospace font with ligatures I could never go back.

Best font + terminal combinations to try this with?

I use Kitty with Jetbrains Mono

I've been using Fira Code.

Speed. A terminal’s job is most just to print text on the screen. You might be surprised at just how slowly that can be done.

Never had a problem with xterm's speed. In fact, it seemed snappier than gnome-terminal, especially when maximized.

Yea, xterm certainly isn’t the worst of the lot.

Hey, use what you like!

As the terminal is the most used app for many here, it's natural for many to care about the small details.

Aesthetics and speed are important to me and to that end Kitty is my choice. Not that there's anything wrong with xterm

Tabs, panes, scrollback search, if you're not using tmux & co. (not talking about alacritty, but about more advanced terminals, in general).

Clickable links.

There is also the transparency support, colors. What I liked with Termite was the Vim-like navigation and mode (visual mode, selection mode, insert mode). It's both useful and pratical. Also, Termite was simple, fast and small (in terms of number of lines). It doesn't come with features we don't need.

I switched to termite when I rethought my setup to minimize my usage of the mouse. I don't think I would have changed for cosmetic features or benchmark reasons.