The 1 mana rebate from Ur-Dragon makes this a considerably more worthwhile card to consider, as a 6 mana 4/4 haste, and adding the additional mana is good ramp for a deck with many expense cards in it (big surprise there)
As with several other artifacts in this ranking, this Swiss Army Stick wouldn't earn any gold stars just by its card-drawing power alone but the ability to manipulate the board at instant speed, and being able to eventually provide card advantage when that's the best option, does make Staff of Domination one of the best artifacts that can draw cards in MTG
There are plenty of great cards to snag, like Relic of Progenitus or Deafening Silence for stax or Nurturing Pixie to reset the Hulk
If you need board-wide double strike, True Conviction, Akromas Will, and Rage Reflection are all options Id prioritize if I had no use for the tutor effect
We skip our draw step anyways with it, and at our upkeep we draw the difference from our hand to 7