Okay, hear me out: it takes so much work and time that not a lot of players feel it’s worthwhile pursuing. But, and please correct me if I’m wrong, but there’s not a limit on the amount you can acquire.
I don’t really expect anyone to agree with me, but let’s say, for argument’s sake, someone put in the effort to replace ten, or even twenty, Shrines of Knowledge. Never mind how realistic you think it is, just bear with me. Greater Runestones have a forge point per square concentration that can only be rivaled by most Great Buildings after leveling them dozens of times. And each one is also adding offensive modifiers and goods production, little by little, packed into a very small space.
The necessary effort notwithstanding, I think Greater Runestones will prove themselves the best building in the long run.