Something else I've been noticing is a misconception about the proposed cost of metamorphosis. I, along with the other serious proponents of metamorphosis, seem to agree that the price of metamorphosis should be very high, probably in electrum terms at 20000-50000 per metamorphosis, while also having the possibility of other non-electrum costs. Few people are really advocating a cheap or easily accomplished metamorphosis, those people saying it should cost 3000 are simply unrealistic.
This system would not be intended to allow people to metamorphosize nymphs on a whim, it would, ideally, force players to spend at least a few days thinking about which nymph they want to change for which, and some serious time in actually getting the required resources. Heck, even I would oppose a cheap way to metamorphosize nymphs, as that WOULD take away from their rarity. However having metamorphosis be possible, albeit extremely difficult and expensive would not take away from nymphs' rarity.