Tyranitar is immune to Wobbuffet anyway so long as it uses only special attacks (unless it Mimics DynamicPunch I guess? Pfft.). So yeah. I figured Quag was going to be the new minimum, it's the proto-Swampert. Surf -> Ice Beam I'd prefer for actual use, because relying on DPunch to hit Steelix is worse than relying on Rock Slide to hit Egg.
On topic: I agree with the removal of D-rank. Browsing through C, I can see what most of their niches are (Ampharos has Punches, DrumZard has the golden OHKO on Skarm/Lix/Forr, Clefable has Drum+Moonlight, Espy has GrowthPass and isn't ruined by Raikou (Vap hates Thunder, Jolt hates Roar) while also having different STAB to the usual GrowthPass target (Zapdos), Golem is just instant offense (and it even Spins!), Houndoom has SunnyBeam and Pursuit, Jolt's a versatile passer that only really hates Raikou, Kangy has CurseSubRoar, Porygon2 is the only non-Uber CurseRecoverer, Quag Drums vs. Electrics, Smeargle DrumPasses or TrapPasses and has Spore, Tenta has that cool Sub/SwordsDance set) but I'm kinda confused what Meganium and Muk have. Meganium is in most respects a bad Egg (Egg gets Synthesis and Reflect too, remember!) unless it goes Swords Dance which sucks anyway (You want a reliable setup with instant recovery? Go P2, it has STAB and isn't running out of recovery PP. You want a dangerous setup with instant recovery? Go Clefable, which isn't hardwalled by Skarm and again has STAB.). Muk... all it's got over Lax is poison on its STAB move, and you're certainly not dropping Snorlax for that. I guess its niche is being a mini-Snorlax that isn't named Snorlax and thus can be used when you've already got Snorlax? Kinda seems weak as a "niche".