I used to use `skim` a fair amount, but over time I've gradually found myself defaulting to `fzf`, but YMMV. I haven't personally used `exa`, but I do like `lsd`. I would also vouch for the other three tools mentioned by eerrt (`ripgrep`, `fd`, and `bat`).
https://github.com/sharkdp/fd/ https://github.com/sharkdp/bat https://github.com/BurntSushi/ripgrep https://github.com/ogham/exa