zsh can replace special variables like `!!` and `!:1` inline when you hit Tab. Or, if you hit Enter, it won't execute the command itself but prepare a new prompt pre-filled with the same command and all special variables substituted to their values. I don't really know how it works in zsh (bash for example doesn't warn you and just executes the command right away with the actual values in place), but anyway it may be more seamless than opening an editor.

Is there a cowboy mode, where I can skip this step and 'just run it'? (excuse me if this is mentioned in the docs)

It's too early for cowboy mode. The LLM isn't reliable enough to let it run commands without approving them first.

As others noted, "try" could be used to make the commands testable, so I'll look into it this weekend.

Doesn't look like it.