Perhaps, what the architect does is they manage a building project - the player indicates that a building should be created, this initiates a series of logistical tasks, made more efficient and thus less micro-managy for the player by having an architect (or given the role, it should be called a foreman or something to that effect). If we think of the architect as an agent whose role is to physically go out and organise the project we get a far more active role for the class that doesn’t rely on merely giving building speed stat boosts.
When we place a blueprint, we could have the option to assign an architect to it; the architect will then go to crafters, notably the carpenter/potter, and get them to craft all of the items which will be required for this project to be completed. This means that the construction can be completed without the player worrying about missing items. I saw another thread about items being automatically crafted when a building is plonked down - it seems that associating this functionality (which is desperately needed if a 100+ city is to built in a game) with the architect and having the visual feedback of him/her directing crafters could streamline the construction process while also beginning to transfer more autonomy to hearthlings (as is necessary for larger kingdoms).
Introducing this kind of class as a mid-game sort of thing has the merit of making larger cities more tenable and less micromangment heavy (think of it is as player neural cost optimisation, something which I would argue is as important as conventional optimisation). As the city grows, the hearthlings become more independent and the player only issues larger commands (though they can still micromanage things if they want) which filter down the civil service hierarchy to the hands that actually do the work, giving them more scope to focus on the macro-game, which should emerge as the settlement blossoms into a kingdom acting as a political entity.
The architect could also manage other things like the availability of tools for the workers, whether all the raw materials are at hand and even when the workers can take breaks (for maximum efficiency i.e. a hearthling working on the cathedral roof gets access to the best tools and nearest eating area since the time spent travelling up and down should be minimised). He/she should also manage how the hearthlings are payed and labour distribution (ask me about this system if you are interested in my hearthling capitalism vision for the larger more reward focused larger settlement).
Naturally, the architect as an organiser should be paired with the “You either designate an area where you want a building, setting a few parameters, wait for the architect to come up with a suggestion and then approve it or dismiss it.” and maybe even other effects.
I feel that the architect can be a role that is not just for the sake of itself, since it lends itself to the macro-game planning and autonomy that will be crucial for the late game. Some people may feel that this is too SIMCITY, however, I was always under the impression that we would be able to create proper kingdoms of multiple hundred hearthlings. Without these kinds of mechanics there can be no macro-game!