With the exception of 672, it's mostly debatable whether those messages should show in the active window by default.
The *status window* exists specifically for response codes from the server regarding commands you've sent it that aren't related to a channel, or are otherwise error messages. Specifically, it's important that the *status* window log error messages, otherwise there's no one place to see such errors. Although it may be unintuitive for things like can't send message, or +g responses, I don't see a problem with the behaviour, conceptually.
I think if anything they should be toggleable, but that just leads to 7 new checkboxes, which is ugly. Scripting it is much simpler.
