This may be a controversial thread because everytime I watch the forum, people is talking about the coin problem. I don’t think there is any, and here I’ll explain why.
First of all, it may be the game design to add a layer of complexity by forcing you how to spend your resources. There has been a long time discussion whether the games should be easy or not. Check Sekiro discussion for example: the game design is to be difficult, thus feeling more rewarding when you actually beat the game.
Here we have the regular PvP game where you fight against people like you. That is hard, and you need to know how to create a balanced deck, think about in-game strategy and win. If we had all the coins we wanted, we eventually be all maxed out and this would the only layer of complexity to the game.
However, this game could be inherently different: it adds a layer le complexity that forces you to spend wisely your resources. You may want to be a collectionist, and that requires a lot of time but feels really rewarding (it is a very hard work and you cannot just pay and instantly get what you want). Or you may want to be at the top of leaderbords mastering just 1 faction and chosing wisely in what units you want to spend your coins.
I think the current state of the game is fantastic in terms of coin income. It allows us to farm something, but enables a mechanism to allow low rank players to keep it up with the daily reward.
Last, but not least, I think devs should focus in creating more content non related to coins, like alliance wars.