Placing information on the back of the card

I am working on a card game where players create a deck of cards by combining 2 sets of : 9 civ cards and 9 magic cards into 1 deck. Civ cards cost 1 gold and magic cards cost 1 mana to play. The card play is similar to the 1 gold in the "Epic Card game"

Now because the cards hold information for 2 card using a card layout similar to the game below:

https://www.boardgamegeek.com/image/3216350/larienna

I do not want to use tapping in my game because it could become confusing. So I have 2 option, place tokens on them to indicate they are inactive (like in Scarab Lords) or simply flip the card face down. Fliping cards seems more convenient and does not require additional components.

I intend to make the refreshing of a card cost 1 gold or 1 mana at the start of their turn. Now the problem is that when the cards are face down you don't know if it cost a gold or a mana to refresh. So I need to look at each card to see which cards I can refresh.

A solution could be to put the type of card on the back so that you can know what is the cost to refresh. I could also place more information like identifying the card set for easier sorting later.

The drawback is that during game play, the opposing player will know if is opponent has civ or magic cards in hand. Players can also see from the top of the deck from which set the next card is coming.

My question is: Does it really matter?

Considering there is only 2 sets, it does not reveal that much information on the content of the card, and both civ and magic cards have the same type of gameplay, so you cannot really predict the opponent's behavior. Since players will draw in average 2 cards per turn, knowing the next card is not that much of an advantage

One thing predictable is since a player only has 3 cards in hand, if he has 3 magic cards in hand, you know he is going to play only 1 card this turn. Else If I have special abilities that trigger according to the type of cards in hand. For example, if a somebody plays a cards that say "your opponent discard a magic card" then the attacking player can know in advance if his spell is going to work or not. Which could be a good or bad thing according to my design objectives.

This is why I am asking because both solutions seems to offer interesting behaviors.

Finally, I could split cards on the side of the deck like shown in the picture above, but cards also have a political and military strength, so players might be more tempted to split their cards according to that criteria instead of the cost.

I know some trick taking games that shows the suite of the cards on the back of the cards, but it's already much more info than mine as those game can have 4-6 suites.

Do you know other games that does that?