The status menu that you can call up with 'z' has a lot of odd choices for information to be shown. There's also a lot of stuff that could be useful there, but isn't... in general, it'd be nice to have one screen with a lot of important stats on it that the player can easily check regularly with one keypress. Right now, it has some stuff that (while useful) isn't something you're going to check regularly -- the breakdown of every type of dwarf, for instance, or the breakdown of where your various types of wealth are. Those things are nice and should be on a subscreen somewhere, but there are usually more important things I'd want to check.
Most importantly, instead of listing the different types of dwarves based on skills, what I'd want is a screen that shows me how many dwarves with a certain job enabled on their v-p-l screen I have. That will let me easily see holes in my labor. (Of course, if this was on a subscreen, it would be even nicer to be able to select one v-p-l labor and see a list of dwarves with that labor sorted by skill or something, with everyone who doesn't have that labor assigned listed after that... and make it so you can turn the job on and off just by selecting a dwarf and hitting enter. But that's something else.)
Another thing I'd love to be able to see is the number of empty barrels / bins / bags in my fortress. Those are important, and it's nice to know when I'm running low before job cancellations happen and things start spilling over my stockpiles without a container.
A list of the number of 'homeless' dwarves -- ones without a room assigned / rented -- would be good, too.
I feel like I've mentioned this before, but it would be nice to be able to get a list of the most common happy / unhappy thoughts in your fortress, sorted by how common they are.
Some of these things could require a specific noble, of course...