Sure, why not. Let's give the users more freedom.
But, if we allow the attribute to be there, we should include them as fields.
If we don't do that, it is better to flag an error.
Otherwise we fool the users to think all worked and later they will be confused as their stuff is missing.

And, 'type' must of course be allowed, but only with the value 'vector'.
[ We could allow 'struct' also, and even 'leaf' if we want to exaggerate a little :-) ]