> a few hundred nodes and maybe 10,000 containers, relatively small

That feels not small to me. For something I'm working on I'll probably have two nodes and around 10 containers. If it works out and I get some growth, maybe that will go up to, say, 5-7 nodes and 30 or so containers? I dunno. I'd like some orchestration there, but k8s feels way too heavy even for my "grown" case.

I feel like there are potentially a lot of small businesses at this sort of scale?