The idea would be to have an option in Metamorphosis called 'Mark Mastery'.
It would cost something in the area of 50,000 coins to purchase and can only be purchased once.
It would make your mark's electrum production x2 instead of x1 for whatever mark you are using.
It would only work against AI, so PVP/T50 it would revert to x1 for that match.
AT first this may seem OP, but not as much as you may think considering you bring out pillars/towers that produce tons of quanta. This makes your mark seem insignificant in the first place. The only thing I see it improving greatly is when you make a duo deck and only have a mark chosen to get out your second colour. One a turn is slow for this as well, sometimes requiring 5 turns to bring out a card.
Also, the FGs have x3 and draw two cards and have double life. This would give us a small improvement against them. It would need to be tested, but it does not seem as if it will make you defeat them much easier. Consider I have a rainbow FG deck and I have tried it with three different marks now and it does not change things greatly, meaning my mark is some what insignificant.
The price makes it unavailable to new players, this is good considering they grind level 1-3, maybe 5 and it may make a significant difference at that point. Later in the game when you have upgraded pillars and cards I find the mark becomes UP.
Last thing, it would allow for new deck creation as certain combinations may be more viable.
Discuss, I know this may sound controversial.