Well, I usually only play EDH so I might see things different, but for me the card looks fine.
Faithless Looting has beome banned in modern, so this card could (somewhat) compensate.
+2/+0 first strike and trample also seems a great package for agressive stategies.
the ultimate may not seem that nice on the first look, but I think its worth it. With Izzet you usually play agressive. the ult gives you 4+
x damage and 4 additional cards which could contain the necessary burn spell to finish off the game. I also think that the package as whole needs to fit. and a cmc 3 walker with 5 loyalty, 2 good +1 abilities and a at least decent ultimate seems like a very solid package for me.