[jrockway]

For me, reverse proxy capacity is more about surviving machine failures. I'll need N+2 of them per region per zone regardless of how efficient they are. For my simple personal site, I run Envoy on 3 machines limited to 64M of RAM and it easily supports 10,000qps per instance with many more concurrent connections (for clients downloading the requested document slowly). One instance alone is enough for all the capacity I desire (and I have rate limits to prevent one IP from using more than its fair share of the limited capacity), so I pay for 128M of RAM that I don't need simply to survive VM failures during a deployment.

I guess my point is that even an inefficient proxy is going to be light on resource usage, and you will always need extras. At some scale, the inefficiency matters, but at most scales it really doesn't. So if Caddy is easy to operate, I'd say go for it. (But personally I use envoy + cert-manager. More flexible and less magic.)