In all honesty, Cleric Sylveon will, for all intents and purposes, completely invalidate the Cleric Florges set, and possibly Florges itself entirely. This was discussed to death in the OU forums eons ago in early XY, but Sylveon is practically superior to Florges in every way. Even though Florges is slightly bulkier than Sylveon specially, the difference in bulk between them is minimal due to Sylveon's higher HP, and Florges fails to wall anything that Sylveon already cannot. Sylveon also has bigger Wishes, a much stronger STAB (Pixilate Hyper Voice), and better physical bulk. Florges is faster than Sylveon, but to respond to a previous post regarding their base Speeds, this actually is completely irrelevant due to the manner in which both of them play. Florges's higher Speed rarely, if ever matters considering it doesn't make up for the advantages Sylveon has. Here are some calcs to show the bulk differences and the power differences between the two:
First, physical:
252 Atk Life Orb Krookodile Earthquake vs. 252 HP / 252+ Def Florges: 181-214 (50.2 - 59.4%) -- 80.1% chance to 2HKO after Leftovers recovery
252 Atk Life Orb Krookodile Earthquake vs. 252 HP / 252+ Def Sylveon: 187-220 (47.4 - 55.8%) -- 21.5% chance to 2HKO after Leftovers recovery
As you can see, Sylveon has slightly more physical bulk than Florges, to the point where it has a greater chance of avoiding a 2HKO from something like Krookodile than Florges does. The difference in bulk here is minimal, and Sylveon has the bigger Wishes so it wins here defensively.
Now for special:
252 SpA Life Orb Heliolisk Hyper Voice vs. 252 HP / 0 SpD Florges: 117-138 (32.5 - 38.3%) -- 2.2% chance to 3HKO after Leftovers recovery
252 SpA Life Orb Heliolisk Hyper Voice vs. 252 HP / 0 SpD Sylveon: 134-160 (34 - 40.6%) -- 44.1% chance to 3HKO after Leftovers recovery
Okay, Florges has slightly more special bulk than Sylveon, but as you can see the difference in bulk is incredibly minimal, to the point where Florges takes around the same amount of damage from most special attackers as Sylveon. And of course, Sylveon has the bigger Wishes.
Now for being able to hit stuff:
0 SpA Florges Moonblast vs. 8 HP / 0 SpD Mega Abomasnow: 109-129 (33.7 - 39.9%) -- guaranteed 3HKO
0 SpA Pixilate Sylveon Hyper Voice vs. 8 HP / 0 SpD Mega Abomasnow: 132-156 (40.8 - 48.2%) -- guaranteed 3HKO
There is a pretty notable power difference here. Sylveon's minimum damage output is almost equal to that of Florges's maximum damage output, meaning Sylveon can even possibly do a bigger dent with SR taken into account. Sylveon also has the luxury of being able to bypass Substitutes, whereas they can be used against Florges to use the thing as setup fodder.
So basically, Sylveon would for the most part invalidate usage of Florges. If Sylveon does end up dropping, I'm almost certain Florges would fall to RU and lose whatever viability it has. That being said, Sylveon itself would be incredibly good, and considering Florges is a Top 5 in usage Pokemon, I'm sure Sylveon would definitely replace it there. Its cleric set would be pretty great and the Specs set would be devastating considering its raw power and incredible typing.
Conkeldurr is also in it for a drop, and I think it would make a pretty fun addition to UU. It would be a great bulky Fighting-type, and it would definitely drop Machamp usage as it's a bulky Fighting type with the advantage of two things: Drain Punch and Mach Punch. Admittedly, Machamp's No Guard DynamicPunch is a lethal tool, but it's nothing when you compare to Conkeldurr's ability to hit something hard and heal itself, making it pretty impressive, and Mach Punch to easily finish off something like Krookodile or Heliolisk when in need. It also has a strong Knock Off, and having offensive recovery and priority would also make it a neat Bulk Up user as those two moves would make it resilient and effective. I think some of the sets it would have are Sheer Force+LO (neat set that can heal itself with Drain Punch and use elemental punches/Poison Jab and hit damn hard), AV (kinda bad but it wouldn't do badly against offensive teams, it would be a nice pain in the ass actually for such teams), Bulk Up, and CB with Superpower.
That being said, I'm sure both Conkeldurr and Sylveon would be really good in UU if they drop, though at the same time, considering what they do, they would also probably invalidate Machamp and Florges usage and send both of them to RU, essentially replacing both of them in their uses in the tier.