It will be strange to play without Ultra Ball (if not downright annoying at first) but we also have: Nest Ball, Pokecom, Net Ball, Treasure, and Electromagnetic Radar. (And fossils.) I guess TPC wants to change the game so that not literally every deck will have the same core cards. Could actually be interesting. Or maybe the meta will only consist of Pikarom, (Radar) Malamar decks (Treasure) and Buzz&Phero (Net Ball).
Field Blower is not that big of a deal since it hasn't been that popular for a while anyway. Loss of Max Potion, E. Hammer and Acerola could make stall and distruption even weaker. Then again, without Zoroark in the format I guess DCE will not be that popular anymore either.