I use Manjaro Linux since many years as system rescue toolkit without network access. In general, I am very pleased with the software collection, which is provided by the ISOs, but TestDisk is painfully missing. It is universally useful, small in size, and has few dependencies, so it should be feasible to integrate it into the ISOs without losing too much space.
Before someone is mentioning it: I am fully aware of the existence of SystemRescue as a Linux distribution with this purpose, but it has several shortcomings in my particular case like seldom updates, a smaller software collection and only one desktop environment.