64-bit ARM as a Tier 1 FreeBSD architecture is on the roadmap. 32-bit ARM will get there too, I think, bit it's not being pushed as aggressively.
it'd be nice if NetBSD was available from these cloud providers.
There is a thread in their support forum, it seems like they want nbd rootfs. It is a pretty simple (not very good) protocol (from memory) but I dont think there is a BSD driver at present.