Sorry if any of these were mentioned before.
Game History: Not as in what games you've played but as in what cards were played. Things can go too fast (more so vs computer then players) and it can be hard to tell what card was played or upgraded. There should be an indicator or a history window in the match so you can see what happened. My two cents would be to have a vertical bar on right side showing the the last turns actions.
Card Types and Level: So these need to be made much clearer at a glance without going into the card details. The card level blends into the background of so many cards that the current graphics are not that helpful. It would make way more sense to have quite different icons for levels. Using this image just as a guide:
https://i.pinimg.com/originals/d1/84/19 ... 6dccba.gif
It would make way more sense to use Private, Captain, and General of the Army, these would be extremely hard to mistake for one another. As for the type of unit it would be nice if there was an indicator at top right of card (same icons that are used in the deck menu would work)
PVP matching: I'd like to see an option to avoid an opponent you've recently played, maybe a time limit like 2 games in two hours, if you hit game #3 you get the option to find a new opponent.
10 or 5 percent raid locks: I think it would be a nice feature if the platton leader could enable a raid lock. This would lock the raid so that only one player from platoon can participate at a time. This could be setup on a percentage of health left (5 or 10 percent would work). This could allow the raid leaders to ensure no one is wasting tickets on a raid a another platoon member is already on the verge of finishing. OR at least have a counter when you pick the raid showing amount of platoon members CURRENTLY playing said raid.
Chat: We need a way to link cards in chat, it would make talking to other players about various cards a million times easier.
I'm sure I'll think of a lot more, I just wanted to take a minute to write these out.