I’d actually like to see the Engineer become a separate, base-level class (still unlocked through a high-level blacksmith building the trinket.) My reasoning is this: first off, the engineer works in a different domain to all other crafters, everyone else builds largely “static” designs with few moving parts – a hinge perhaps, or sliding drawers, but nothing like cogs or the presumably more advanced stuff coming in the Engineer’s future. Secondly, it already takes a lot of effort to provide the iron and bronze bars that an engineer will need for their early constructions in order to “train up”, but if the engineer also has to reach a couple of levels in another class first that increased experience cost per level-up makes the task even more difficult. Currently, by the time I have my engineer leveled up to the point they can make traps they’ve already made enough cogs to build all of the traps and turrets they need to fill out their caps, plus a couple of spares, so if I want to train more engineers in order to have more traps/turrets that means a rapidly growing stockpile of gears.
I reckon that starting the engineer as a base class alleviates that problem a bit, and then the mining task can be removed from the engineer’s list of jobs to put emphasis back on it being a building class. The blacksmith might even be able to create the wrench a bit earlier, so there’s a better chance to have an engineer before you’ve hit “late game”. It would make a lot of sense if some of the more advanced tier 3 items (particularly in the Ascendancy’s military path, and the Rayya’s Children path which unlocks all those fancy architectural items like large arched windows) are constructed by the engineer; but for other paths the engineer doesn’t have nearly as much to do… in fact unless the class gets some amazingly powerful machines to build or other abilities, I can see some players doing without it entirely, particularly if they’re building a “self sufficient” town (e.g. Hearth of Cheer where the town is able to provide all its own needs and focus on stability and happiness.)
While the subject of late-game engineer constructions is up, I’d also like to suggest giving the engineer some earlier “experiments” to build – they could be largely decorative or joke items which the engineer is using to test out theories, before using what they’ve learned in “proper” creations later. The turnip shooter is a perfect example – I can imagine that the engineer was inspired by a chunk of food being lobbed across the dining hall by the levering/trebuchet action of a spoon, which prompted the construction of the experimental turnip shooter, and then eventually leads to the “proper” turret. At higher levels the engineer might refine the turret further, building a larger ballista for taking down heavy enemies, or some other improvement on the design. The same might be the case for pumps later on – the first experiment could be a simple fountain which is merely decorative, but later we see powerful pumps to drain lakes or clean up floods. Or even think of something like Newton’s Cradle, the initial design is merely a proof of concept which makes a cool decoration, but later it leads to pendulums which can allow something like clocks (a much nicer decoration and very expensive trade goods.)