Can you say which properties of macros you're interested in here? Do you really want to do macro-like things in them (which depend on the passed-in tokens, or do caller-control-flow-affecting things), or are you just trying to value-like things without needing to write types?
It doesn't help that you appear to never use $z so I don't know what you mean by it.
If you mean the latter, see also the conversations about a hypothetical "macro fn", like Make macro syntax similar to function - #4 by scottmcm