"smoothly"... Last time I played it, no amount of keyboard jockeying made trading less tedious.

I always thought the hjkl movement for constructing walls and floors was very cool and vim-esque. But then the fact that you can't build a wall with more than 10 segments at a time ended up being one of the most trying aspects of the game for me, where I loved focusing on building a 3-tier outer castle wall with fortifications on the outside with steps going up and down on the inside and my army patrolling along it's border.

I don't really agree. In and of itself the existence of keystrokes doesn't make the UI efficient. There is still a ton of cognative dissonance and unnecessary friction in DF.

Keystrokes that work in one place don't work (or worse, don't work the same way) in another, menu options that are very similar are ordered differently in different places etc. If you learn how to work one aspect of UI (say the millitary menus) you can't transfer that knowledge to working another (say the minecart UX) most of the time. Except sometimes you can, which makes it even more confusing.

And of you don't know the keys the mnemonics are all there on display.

My real gripe with the UI is that it exists in different state of growth, so hospitals are zones but dorms are rooms; I can guess why hospitals were crammed there, likely because the hospital has a stockpile of items and the room menu didn't have the code for that while zones, which handle stockpile, did, but still.

Learning all the shortcuts isn't really the challenging part of learning DF, the underlying mechanics are often just as baffling.

For example the distinction between "Rooms", "Zones", "Stockpiles" and "Locations" which are all just variations on "area marked for some purpose" but that all exist as their own independent concepts and are specified in different ways.