I agree that doing this from the start would have worked, but that doesn't mean that it necessarily would now.
It comes down to why people choose to build the set. If goods production is the reason then I'd expect far fewer scrolls boosted players to currently have the Moonstone buildings. If this is true, and we made the above change now, then we'd be left with a deficit of scrolls+1 goods, and a glut of the other two. Of course scrolls players would now be able to address this (by building Moonstone sets), but not if the set is no longer available !
Although the idea in simple and elegant in conception, it might hard to program. I can't think of any other winnable building which (for a given level) has effects which depend on the player.
scroll players as well have moonstone sets. there nice to have. and the best part you only need to reset them once every 21 hours / daily
a new set, event buildings with other bonusses, more things that ask for scrolls (ther is a reason we got this x million scroll thing in I think chapter 16?) none of that are solutions, at best it shovels the issue a bit further ahead of time. also in the long run this will lead to other issues that might be even worse.
modifying the set to bonus +x is the only real mid to long term solution . (there is no short term solution unless we get the opportunity to once change scrolls for anything else at a 1:1 ratio so that all goods are equalised again)
btw: modifying the bonus to +1 is by far the easiest way to prgram it takes a whopping 1 whole minute of dev time.
Getting the storyline in check takes a bit more time as you need to come up with a new storyline that might reuire you to change the visuals of the building, this takes a bit more time of the art department and the writer. for the dev it's another whopping minute to implement once those are done. changing a text of line, or a string to the correct visual asset ain't that hard
You could do it lol.
And we went through this before. There was an older set.. Maybe the jester one? That game out all elixir and we (Beta) had to beg them to change it to boosted +1
all sets in the beginnen had the same output and as you said people already begged to solve it, as it was "destroying the market"
that was when that "problem" was so little that it was "pathetic" compared to the current library set issue.
I have called the library set a ticking timebomb since day 1.
I also have had the opportunity around that time to personally speak with some people that do have (in)direct access to the game designers.
I had explained that this wet was an issue, not now but when more people aquire these sets and build up there own scroll production that scroll players would eventually be placed outside the game as less and less people would need there goods.
As more than often they never seem to fix issues but let them simmer and destroy the game for certain players untill the moment it becomes so severy they can no longer deny it, this is usually 2 years, so i'll guess there quick now.
Then once the acknowledge it, it's obviously still not a priority.
It still took 8 months!!! to show us any sign of change with the removasl of the set on beta.
And that can't even be called a solution