Kraum seems pretty good to pair up with Vial Smasher the Fierce who deals damage to a random opponent for the first spell you cast during your turn equal to that spell's converted mana cost. Kraum draws you cards and Vial Smasher softens up your opponents' life totals. Gaining the black mana is pretty awesome, too.
If you want to draw even more cards, you can Partner him with Tymna the Weaver. She not only gives Kraum access to Black and White mana, but has a draw engine of her own. At the beginning of yor second main phase, you can pay X life where X is the number of opponents damaged in combat that turn. If so, you then get to draw X cards. This seems like a natural partnership to me. Thn you can suit up Kraum and really go to town.
A lot of players have found Kraum, Ludevic's Opus underwhelming on his own. But he has an aggressive body and an ability that can draw you at least an extra card almost every round of turns. He's definitely better with a Partner, but I really just like him overall.