Do such small caps on CPU/RAM mean that multiple customers are sharing the same server? Is there concern for noisy neighbors here, either IOPS or in case another customer's workload grows to take the full available storage on the NVMe? What kind of downtime would be needed to switch to a larger size?

Why is Metal not offered for single instance deploys? Our app does not need this kind of uptime. We would be happy with a node going down once in a while (no data loss, of course) with a little bit of downtime to save 66% on the cost of running 2 additional nodes that will never see action.