Guess I'll examine and analyze the potential drops as they are now:
Goodra: This thing has the potential to be really solid in UU. It has incredible special bulk and solid Special Attack, making it a cool-looking option for Assault Vest and Choice Specs. Sap Sipper is an interesting ability, but UU has a general lack of great Grass-types outside of Roserade, and maybe Celebi. While its physical Defense leaves a bit to be desired, Gooey can absolutely ruin some of the top physical attackers in the tier when you play it right. A well-timed Speed drop on stuff like Mienshao, Victini, or Darmanitan late-game can just end their chances of finishing you off. I don't think it will be broken just due to the fact it's a little on the slow side and UU's top wallbreakers / sweepers are hitting primarily from the physical side.
Lucario: This is something I absolutely predicted when Lucarionite was suspected in OU a couple of months back. Good to see I know what I"m talking about sometimes, lol. Anyway, Lucario seems to fit really well in UU. He has great mixed attacking stats, 3 different boosting moves, and can run different Choice sets as well. SD, Agility, and NP would all be viable imo due to the current state of the metagame. NP would probably be best since Luke's STABs maim top special walls, though its lack of powerful priority leaves it very suspect to being revenge killed. Choice Specs is another set that probably has potential due to its STABs being super effective against top special walls in Umbreon, Florges, and P2. I don't think it would be broken since Luke's frailty makes it hard to setup with and base 90 Speed still leaves it outpaced by some important things, but it would certainly be powerful.
Volcarona: Don't think I need to say much on this. Quiver Dance makes this thing a beast and one of the only reasons it would drop to UU is because of Talonflame and Mega-Pinsir up in OU ruining its day at almost every corner. Were it not for these two, it would still be a solid OU Pokemon. As it stands, it would be pretty damn broken in UU considering it can use the two top special walls, Florges and Umbreon, as complete setup fodder. Definitely BL material if it drops imo.
Alakazam: Mega-Gardevoir 2.0 if this thing drops. May not be quite as powerful thanke to a lack of Pixilate, but it's much, much faster. Trace can also make this thing crazy hard to take down. Ever thought Gardevoir was a pain to take down if it Traced Sheer Force from that Nidoking or Nidoqueen that just KOed something? Yeah, imagine this thing after Tracing Sheer Force. About the only thing that would have a shot against it defensively is Umbreon since Focus Blast is so notorious for missing and Ala would have to hit two of them in a row to beat Umbreon. Otherwise, Psyshock + Focus Blast deals with most special walls / tanks in UU right now. Definitely think it would be BL if it were to drop.