I would definitively support the idea of having a switchable building.
But the problem with the libraries is, that they are still polluting the global trade and thus ruining the game for everyone. Yes, they did fix the standard goods. But by now, the ascended goods are just as big a problem. So it is not really that there are to few fragments and that we cannot craft enough. The problem is fairness. Players shouldn't be rewarded for polluting and thus hurting others. So the developers should be looking to make libraries obsolete and not make them ever more profitable by increasing the fragment demand.
This is also the reason, why I will not accept arguments like "just disenchant instants". The instants have a value. Why should we have to pay with them when the polluters get everything for free?