It'd be neat if you could create macros that have variables built into them! It'd be really handy for making your own custom directed emotes at the very least, or if you wanted to quickly clear your SIC tag and quickly switch to a new alias that you specify!
You could perhaps specify the argument in the macro itself with some placeholder like "%arg", which gets replaced with whatever you follow the macro command with. So, if you wanted a macro that makes you point dramatically at someone (let's call it "~dramapoint"), you could have it as:
.strike a pose and .point dramatically at %arg
And then when you type "~dramapoint Steve", you'd get:
"You strike a pose and point dramatically at Steve."
It could also help for shortening commands: I.E., "drive katana to %arg" could be mapped to "~d", shortening the command for driving your motorcycle to "~d w w n e" to drive west, west, north, east, etc. instead of having to type the entire phrase every time.
I get that macros are supposed to be pretty bare-bones, so I understand if this is asking a bit much, but it's a little piece of functionality that I find myself wishing I had access to when thinking of what macros would make life a little easier for me.