A much maligned 'feature'.
A Player-controlled to the extent that they can determine which moves to make when but not the sorts of situations and frequency with which they might make them. Some parts of play are move heavy, with lots of snow balling and such. Others are lots of saying yes and exposition.
Having played and run a great deal of AW and now some DW, I find the Highlighted stat thing to generally be unfun for my players. It's uneven, often forgotten, and gives extremely uneven advancement within a group. The idea only works if player's actively pushing to make Moves with the highlight Stats and are focused on or mentally prioritizing advancement. This is great for aggressive players that are constantly seeking to engage the mechanics and don't prize consistent character immersion. However, I find that it's typically one-in-five of people I've actually played with. Those same people are typically people who are also GMs and also post on internet forums about RPGs. They aren't my typical players, though. For the casual or character driven player, it's a headache and distraction.
Having it be a Spent-Gold-for-XP thing means that the whole XP thing is taken care of during the shopping downtime between adventures and remains largely abstracted. It also reduces handling time while making moves and keeps moves about the fiction and not pressing to make move to get XP. Plus it's a core motivation for the whole dungeoneering thing.
The Alignment Keys are great though. You get to pick them as a player, helping you inform your character vision, and since they're simple, fixed and mechanically isolated, they're easier to keep in mind. But there's not much of a penalty for ignoring them if they're not the main source of XP.
If it ain't broke for your group, that's cool but it's been a really great patch for they people I play with.