I don't like the ability, at all.
Making your pillars into nymphs sounds good, but nymphs are only dangerous with their abilities, with few exceptions.
To get the nymph you want and to be able to fund the ability reliably, specific elemental pillars are needed. The more quantum pillars this nymph relies on, the more luck gets involved.
I would be more than willing to use a nymph like this if it had an ability I would use, and even if it got a buff in stats, I'm not sure I would use it, until it just became a good fighting creature, which isn't really the point.
At the same time, the ability can't be TOO good. The idea of a purify nymph is tempting, but it would totally destroy poison, as well as giving as much healing as it would be possible to have, restricted almost totally by the number of turns your deck could last.
I would suggest making a new water card, so that the nymph for water still uses a spell from the element.
Reflecting Pool/Mirror Pool
Cost: 4
/3
Effect: Transforms one of the enemy's permanents into one of your permanents
This could affect pillars, shields, weapons, or other permanents, but always to the same type (so quanta generation, towers/pillars/pendulums can only turn into quanta generation) and could potentially change it into itself (just as discord can turn quanta from one type into the same type), so not overly powerful, and benefits water based decks, and not so much rainbow decks that would be likely to make a quantum pillar for the other side.
Then, give the water nymph this ability, for 3
.
This would be something I would want to use, but I can't imagine it would be too strong, just disruptive, like the other nymphs.