Another card that encourages coding 'Target element' and is a flexible multi-element splasher? I like it.
I think stacking is fair but I don't think you should be able to run more than 6 copies. While 1-cost is useful in making this strictly less efficient than a normal pillar, it's important that basic pillars always play some kind of role in how you deck build (there's a reason MTG only lets you run 4 of every nonbasic land as opposed to its 5 'unlimited' basic lands.)
I see your point wrt. MtG (which I used to play quite frequently) ... however, MtG has a VAST cardbase and is constructed with such in mind. Also, MtG has fewer elements, and its mana production scheme is significantly different.
I don't think the quantum generation rate needs to be sped up in any way - at 1-3, 1 quantum of any desired element is probably okay (unless you have a trio with a small splash) and by 4-5, you should have your 'domain' of elements set up, making this somewhere between a normal and quantum pillar in terms of the 1:3 ratio (which makes sense since you're not using all 12 elements.) I doubt you'll ever go beyond 6 elements on this pillar - quantum pillars are probably just better at that point for faster generation.
so I should go with:
0 => 1
1-3 => 1
4-5 => 2
6+ => 3
correct?
Seems reasonable enough to me
So the question is, will this card be more valuable than regular pillars in current deck archetypes to the point that it starts replacing standard pillars?
Certainly for mono's and duo's, players are better off with pillars since they will be more quanta efficient.
For trios through pentets, these pillars will provide more stable quanta, but will take a few turns to get running.
Since double production doesnt start until the 4th quanta type is picked, it will take a minimum of 4 turns to become more efficient than standard pillars or pendulums.
Lastly, the unupped version will be hampered by the need to provide quanta just to play it. The unupped will not, but they will still produce more slowly than Towers which provide immediate quanta production.
All that given, however, it is possible that these will still be to potent compared to standard pillars and pendulums due to their flexebility... Anyone know of a good way to test / analyze this?