Honchkrow + Flame Charge: This is my slate submission, so I'm gonna post the original explanation I gave for it, verbatim.
Solid mixed attacking power, a powerhouse of an ability, and enough coverage to keep itself afloat in the meta (only on paper), but its piss-poor defenses, bad speed and lack of useful boosting moves outside of Nasty Plot (which it can't even use well, due to no synergy with Moxie and lack of Hurricane/Air Slash) let it down immensely. Flame Charge seeks to remedy that by giving it a helping hand against faster threats, thus ensuring that it doesn't need to rely on Sucker Punch all the time (which is one of its biggest issues in OU, after everything I just mentioned).
It's not overly powerful without a Moxie boost, but the speed boost ensures that you can't just whip out an offensively-oriented Dark resist and force it out, since Brave Bird still hurts at +0. What really sells this is its utility as a powerful Pursuit user that doesn't need to rely on a Choice Scarf to answer things like Latios effectively. Furthermore, unlike Bisharp, it offers role compression as a sweeper and Pursuit trapper, since Scarf or BandTar obviously can't boost up, and SD is far more used on Bisharp than Pursuit, and are rarely combined (and even then, they don't offer the speed that Honchkrow can with Flame Charge). Flame Charge, in terms of the coverage it provides, is also largely the same as Heat Wave, but the only thing it sacrifices is the OHKO from Heat Wave after SR on 200 SpD Mega Scizor, and that requires a Naughty nature and not Adamant.
Obvious downsides are that it can't get past Lando-T/Chomp/Hippo, but it has Icy Wind for the previous two on the switch (which is a guaranteed 2HKO even with an Adamant nature), and it has absolutely no business staying in on Hippo anyways. Its weakness to priority is rough, but there's not much that's able to be done about that with moves/abilities alone, considering Gale Wings is a stupid mindless buff, and priority users are often gunning for the revenge kill rather than risking a switch-in into a successful prediction (read: Weavile, Azu, Scizor).
Cofagrigus + Recover: Ah, now this is the slate change I was looking for. Mono-Ghost is a surprisingly effective typing, and Recover only seals the deal by making it a full stop to ability-dependent physical attackers. Nice and meaty counter to a huge number of Fighting-types and Band users (ex. Azu) in the tier, but definitely still balanced due to its low base HP and somewhat lacking SpD. Personally, I wish it got some coverage as well, to make up for its piss-poor offensive presence (something like Focus Blast or Flash Cannon), but that's kinda just hopeful thinking. Hyped for this one.
Tauros -> Normal/Fairy + Play Rough: I like the addition of a move that benefits from Sheer Force, and Normal/Fairy sounds nice, but I don't think it fundamentally solves what's wrong with Tauros in the first place, that being the fact that it has solid coverage, but it's forced to use its absolutely horrendous SpA stat to make use of it. It has chronic trouble with bulky Rock and Steel-types, which Play Rough does nothing to solve (hell, it even makes it weaker to Steel-types, given things like Bullet Punch), and is just too weak against physically defensive things like Lando-T and Slowbro because of its poor type coverage on the physical side. Its stats actually aren't that big of an issue considering that it has 100 base attack to Feraligatr's base 105, and they're both Sheer Force users. Tauros also has the honour of being the fastest Sheer Force user in the entire game. I can see Fairy coverage helping against things like Keldeo, Terrakion, and a good number of Fighting-types aside from that, since Zen Headbutt does not OHKO either of them and STAB Play Rough does. Personally, I would have given it a more convincing move choice for OU, like Flare Blitz / Icicle Crash or something. Fairy's nice, and actually gives Tauros a niche, but I don't think it's a big enough niche to matter due to how hard it is to pull off and how reliant it is on revenge killing.
Yanmega -> Bug/Ground + Earth Power: I think I remember this from a slate long past, and I don't have too much of an opinion on it. I like the TWave immunity, rocks mitigation and Heatran-killing power, so I genuinely think that this can take off. Ancient Power, while it helps against Flying-types, doesn't seem like the most reliable of moves to run due to low power and PP, and it also suffers from being weak to Aqua Jet and still taking a lot from resisted Ground moves due to its poor defenses. Overall, I'm on the fence with this one. I love its coverage and typing boons, but the limitations in those same things hold it back for me.