I've always just used konsole or gnome terminal. Never really looked into what else is available. Tried cool-retro-term the other day, but the novelty wore off pretty fast for me.
Curious to see if there's a terminal someone swears by and refuses to use anything else.
There are a small number of terminal emulators I would be happy to use as daily drivers and most of them have been named here but my default is kitty. It supports everything I need and a lot I don't and doesn't have any showstoppers. All the modern terminal implementations are performant enough. I used real terminals like vt-100s and vt-220s. Everything we have today is awesome by comparison. We fetishize performance and features too much. Once you have something that works there isn't much reason to change IMO.