Show the season card back rewards to motivate players
In the profile screen it shows the season rewards but does not show the card art style you'll win (this season it's the Recruitment Officer card style + Brotherhood's End card style). I had to find this information by searching for news articles using Google!
This is could be an oversight because I love playing Grixis and therefore wanting to win the Brotherhood's End card style is the only reason I'm playing ranked this season. Therefore, if you let players know what card styles they stand to win, more people would want to play ranked and play MTG Arena. Everyone likes winning stuff they want!
The fix is relatively straight-forward - the card style rewards could appear on the Profile tab when you click on your rank badges. I have a screenshot of where they could appear. However, if I were you, I'd put them somewhere it's easier to see than there because this screen might not be intuitive to find for everyone.
Also, including this information in MTG Arena would reassure players because journalists aren't always correct.