Aristos
Lightseeker
Worker micro was a huge skill variance source in Civ 4. For Civ 6 this is also true because of how your charge count is variable.
The requirement to repeatedly make more with no queue/broken city UI is a chore, but this is not a fault of the builders, just the broken UI. I wouldn't mind seeing this be integrated into city management, but it would be a pretty heavy rework to accomplish about the same decision making. My vote would be to save that for Civ 7 and just make the UI in Civ 6 work first. The builder design aspect is pretty good.
Though the tradeoff between harvest and make/leave improvements is still borked and I'd like to see roads matter more sooner.
The thing is that they went halfway to a better solution (which, sometimes, seems to be their sport). You can "feel" the CTP spirit in the builder system, but as anything half cooked, it remains wanting... the builder system is just a production --> infrastructure system, exactly as it was, although much more elegant and efficient (and straight to the point), in the CTP series. The problem is that in using a "builder" unit to convey that conversion, they added: a) some useless micro, and b) constant production costs for everything. The latter, in particular, is bad and a wasted opportunity. I much prefer the CTP system where every infrastructure has its cost in hammers, different and evolving with the ages, and you pay for them from real, pooled, accumulated hammers that you had to divert from other tasks (via slider, oh the horror).
But hey, let's not apply good lessons from the "enemy", right?