I sympathize with those who say this needs to have only positive effects(ie. generate your quanta not just what the opponent spends) but doing so might make this too powerful, particularly as an other card.
Also as a personal vendetta, anything that empowers rainbow decks, which this currently does more than anything, should get thrown away...
...I don't think any card that might potentially help rainbow decks should get thrown out, just those that strongly favor them over other strategies. This typically means most
cost cards since they strongly favor the raw quanta production advantage of rainbow archetypes.
As for being too powerful as an other card... I agree that this could be a problem. This card could be very potent if a player can too freely choose where the quanta goes to.
One interesting way around this would be to have the card only generate quanta of the owner's mark.
Another option would be to have it target a pillar or pendulum when cast and give back quanta from that type.
E.g. rainbow decks, which tend to only have quantum pillars would get back a random distribution of quanta. Mono's and Duos, however, could get back quanta of useful types.
The pillar / pendulum targeting version could actually be a very useful in making trios and quartets more stable since they could use it to balance out whichever quanta type they are short on.
Rainbows would actually benefit least since they would have little control over where the quanta goes too.