firstly, you were complaining about quantum pillars/towers being overpowered... Quantum pillars/towers are very good in the way that they give 3 quantums per turn...but the quantums are random, which slows down rainbow decks considerably in many cases. Also...you said "5. Rainbow on the other hand gets 3 random quanta from one p/t by turn, so with 4 on the table we got 1/1 mathematical chance to get 1 point of quanta we need to use on ability." This is badly flawed... you say mathematically it is a 1/1 chance, meaning 100%. If you get 12 random quantums per turn, you almost never get 1 of everything. The chances of not getting the quantum you want (if you only want 1 of it) is 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 x 11/12 (or 11/12^12) which works out to be just over 35%. That means you have just under 2/3 chance to get the quantum you want, which is a relatively good chance, i admit, but quite a ways off of 100%. Also, most cards in a rainbow deck have a relatively high cost, meaning that with 4 pillars/towers, it can take an average of 5 turns or so to play an upgraded bone wall or graveyard. Also remember that, while rainbow decks can take advantage of the best cards from every element, they also are stuck relying on some of these cards, or the card's abilities. For example, many rainbow decks will have only 1 ffq, or 1 oty, or 1 fallen druid etc. Now if you kill their only ffq, oty or druid, they will have a severe disadvantage. Likewise, if you destroy their card-drawing permanents, they probably won't draw their oty/boneyards/ffq's/druids at the same time. This is one of the major disadvantages of a rainbow deck.
all in all, yes, rainbow decks are powerful, but they are mainly designed for god-killing, where the opponents have predictable decks. In pvp, one important creature dying, or 1 permanent being destroyed can cost them the game.
