Nomad supports all sorts of architectures and OSes, including M-series CPUs and MacOS. It can also scale to a lot, 2 million containers being tested. [0]
In terms of autoscaling there's the Nomad Autoscaler[1][2] that is super flexible, can get metrics from a bunch of sources, do custom queries, and perform actions (everything is via plugins, so even if your current stack isn't already supported, it's easy to add) like add extra nodes or add more instances of jobs.