Magic was and always will be about creating decks and the most fun thing to do to aid you on your quest for the best deck is getting cards by all means possible, in paper magic we buy and trade cards.
In arena we should be able to trade cards and convert wild cards for another rarity.

Imagine if we could trade cards and wild cards with friends, that would be awesome. And if you don't have any friends maybe you could convert your 100+ commons wild cards into rare or mytic ones.

Should be in place a conversion rate and if you trade with friends you have to pay a small fee in gold coins.

I think this feature will give Arena the nostalgic feeling we are looking for and help new players.