DF does have very impressive depth and game mechanics. Unfortunately, its interface is one of the worst of any game I've ever played.
It's a pity that DF isn't open source either, as then its interface problems would have long since been fixed. But, as it is, its lead (and only) developer doesn't seem to care enough to fix it himself.
The interface for DF is actually not bad at all. Once you learn the keystrokes the interface disappears, and you don't even need to have the side menu open at all except on context menus where you need to scroll up or down. I find it to be vert fast and efficient and would hate the game it I had to use point and click or some other slower method of manipulating the world.
I have learned the keystrokes, and have spent countless hours playing it. The interface is still absolutely awful. It's so inconsistent and needlessly convoluted.
Just to be clear, I'm not wishing that DF had a point-and-click interface. I'm happy that DF is keyboard-controlled. It's just that this keyboard control could have been made a lot less painful with a tiny bit of consideration for consistency and efficiency.
As far as roguelikes go, nethack has a pretty nice interface (except for the stupid # commands), though even there there's some room for improvement. DF should have been modeled on that, or at least with some input from players on how the interface could have been improved.
At the absolute least, the author could have let the same actions on different screens of the game be activated with the same keystrokes, rather than requiring completely different keystrokes for some perverse and unfathomable reason.
Another quite workable solution would be to let the keystrokes be user-configurable. That would go a long way towards lessening the pain.
From what I remember reading when I was frequenting the bay12 forums, it's a mixture of pride (the code is very rough, and it would probably take a huge amount of effort to get it into a form where contributions from others could be useful, or even where others could contribute) and control (he doesn't want it to get out of his control, and as it's his only source of income he doesn't want to deal with donations and community being fractured between several versions). The fanbase both doesn't care (based on donations) and sees it as a challenge (there have been some interesting analyses posted of what the game is doing, and there's a thriving modding community - both in the form of modifications to the game's files, which is supported and encouraged, and modifications to the game through memory editing, leading to the creation of invaluable tools like Dwarf Therapist).
If your only reason for not trying it is that it's not in apt, just go to the website and download it. It doesn't take any installation; just download it, extract the contents, and run the game.
It's a pity that DF isn't open source either, as then its interface problems would have long since been fixed. But, as it is, its lead (and only) developer doesn't seem to care enough to fix it himself.