The "start with 3 gems charged" and the "charge 3 gems faster" are work well together: if you have both in your deck, your rare cards with the same color will be charged before the 1st turn. In this case choose 3 or 4 rare cards with stronger abilities and make your deck complete with 1 or 2 highly upgraded mythic, just include both perks, and you can hit dead a lot of enemies in the first turn. You must have seen that in the Colosseum or in the Tower from some opponents. I use this in the Colosseum now and then and it works fine, but in the tower my cards are not strong enough for it.
Of course you can use the combined strength of these perks only in the same color, which is another nail in the coffin of multicolor decks.