My thoughts on it: Maybe condense upgrades into fewer but more significant packages, with an emphasis of the mansion gradually moving away from generic tasks towards more specialized stuff?
EG: The mansion starts with three broad tasks - Gather, Forage, Household. Gather retrieves stone, wood, and a rare chance of something like iron or a better wood. Forage is all about fishing, hunting, finding wild crops, and the occasional medicinal herb. Household generates money and reputation, maybe a new servant - increasing the size of quest rewards through negotiation, escort services, accounting, socializing, ect. There are no limits on how many people can be assigned, but you can't aim for specific items.
LV2 upgrades add focused tasks. For example, the "Quarry" upgrade allows you to reliably mine stone, metal, and the odd gemstone. Tier 3 allows you to add options for seeking specific items. An alchemist lab for transmuting stone into gold, for example.
Upgrades are not only for empowering players, but also to set a path of progression. The game currently suffers from being a bit hard - part of that comes from having so many choices, it is hard to know which would help in the early game. By having the upgrades route the player's goals, it should be easier to guide the player without tipping the developer's hand.