The art is Alteil is expected to be better as its much easier to produce.
First and foremost, the canvas is MUCH larger than around 1"x1".
Second of all, there are much less strict guidelines in place as they are not physical cards. In magic, card art is done to help people sort and recognize cards from a distance. There's a reason modern cards look so distinct. Its also to help collectors sort their cards faster. Furthermore, the colors usable are extremely limited, as they are placed so close to the colored borders. Having lots of orange and blue on a red card would look extremely unattractive and ... well wouldn't be used.
Finally, they have a LOT more restrictions on what they can and can't show for marketing purposes. They can't have females as nude or provocative as Alteil can, as its a printed product by a "family friendly company" (Hasbro). Finally, they avoid mostly-naked-men as the target audience is males 15-25.
However, there are some aesthetic advantages to magic cards. The resolution is higher since its printed and not your moniter. You can get cards signed. And you can get cards customized or customize them yourself if your a good enough artist or go to conventions where you can meet them. Painted cards are legal so long as you can still tell what the card originally was.
The biggest advantage to magic cards over virtual cards is the simple fact that Wizards can't tell you what you can and can't do with your cardboard. As a result, you can do a lot more with magic cards than you can with alteil cards: Trade, Sell, Buy, play custom variant games, draft, etc...
An Alteil Draft would be REALLY fun...