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`).
* lsd - https://github.com/Peltoche/lsd
* sk - https://github.com/lotabout/skim
* hx - https://github.com/sitkevij/hex