It would be really cool to have the option to toggle small text at the bottom or top of the card that specifies which set it is from. As a relatively new player, I find it difficult to determine which set cards are from when they are older and do not have the symbol or text at the bottom.
top of page
bottom of page
if you are on a PC or Mac, you can turn on the advanced tooltip in the settings and then hovering over a card will give you that info :)