But they're not all included in the same image. We have 8 variants, 6 of which only contain a single language. There is 1 which contains everything, and there's 1 which contains nothing and is meant for customization.
> web server, app server
The web server and the app server are the same thing. Passenger is an Nginx module.
> aux services and tools.
Only the minimum possible to allow regular administration, inspection and debugging.
> First impressions are that this image is one-size-fits-all
But it is not. That's why we have 8 variants. Early in development we've explicitly made this a many-sizes-fit-all thing.
> and that they are disabled by default, but I still feel the balance of the README is wrong as it doesn't sound any kind of warning that you probably don't want to do that in most cases.
Fair enough, though I disagree. I'd rather assume the user knows what he's doing. If he chose to enable Redis then there's probably a good reason for that.