Hexus is just excellent imo, it’s a good size, has good and easily usable tools (including a randomly good chain breaker), basically it’s the right blend of small-ish size and practicality and usefulness, there’s nothing smaller that’s worth the compromise. On the downside it’s a wee bit low quality really, it can rust and come loose over time, but that’s pretty trivial. The tyre levers are absolute crap, but that’s fine, they’re just part of the handle anyway so there’s no loss.
Alien is ideal if you ride something weird or if you think you might want to stop mid ride and build a climbing frame but mostly it’s extra tools you’ll never use, that make the tool itself far worse to use. Crank Bros make lovely tools but they’re never quite as basically practical as the Hexus (wish we could get Crank Bros or Lezyne to make stuff that Topeak design!)