Our House

Our house is a Craftsman style built in 1928. For years it had been a rent house duplex. The house had deteriorated to the point of being uninhabitable by humans. Two young ladies ,along with their mother, bought and completely renovated the house. They in turn sold the house to my future wife, we moved in and got married on the trolley.
This house makes a perfect case study of restoration. Here are pictures of the kitchen before, during and after the renovation.
You can see that they removed the plaster and a good bit of the lath. They used sheetrock to do the walls and ceilings. They retained the original windows. They installed cabinets which came from a modern day home center. The counter tops are concrete which they made on site . The floor is tile. The plumbing, electrical and hvac are all new. The walls are insulated with cellulose.
The house was not in the historic district when they did all this. Their purpose was to buy an old, rundown house for cheap in an up and coming neighborhood, fix it up following a tight budget, and sell the house for a profit. I will say that they were very successful. The work they did on this house was a labor of love. I know it must have been emotional for them to finally sell the house after two years of hard work.
Time has gone by and now the historic district has been expanded to include our house. Property values continue to rise in the district with development projects coming to completion. New developments are announced regularly. As I understand the historic district designation comes from the Department of Interior by way of the National Park Service. I've been told that structures in the district can be torn down on the Twelfth of Never, which is the day after Hell freezes over. This changes the economic equations governing homes here. The historic designation affects things such as loans, taxes, insurance, etc.
Experience taking care of owners of property has taught me that properties take on a life of their own. Structures set aside for perpetual preservation will definitely outlive anyone reading this. Sub par improvements of a lasting nature will have a degrading effect on valuation, therefore on the lives of the occupants. Any kind of improvement project, whether good or poor, will challenge the owners to their limits. Primary improvements should make life better.
Primary structural improvements are absolutely justified. I say this because such improvements are very costly and require the supervision of an Architect and/or Engineer. Is this expense going to be recovered with a corresponding appreciating value? Is the outlay justified?
Will anyone take on this question and comment?