Edit (3/9/2015): For March season, I've swapped out TBK for Harrison to deal with the two matches I struggle with the most: Oil Rogue and Paladin. As a bonus, it also helps against Hunter. It weakens my match-ups against Mage slightly (annoy-o-tron) and Druid significantly.
I played Ramp Druid most of the season with several variants. The tech cards I swapped in and out were MC Tech, Shade of Naxx, and Kezan Mystic. This one pushed me over the edge. It's very anti-Hunter—both types—with big Taunts, 2x Chows, and Kezan Mystic.
It has a good winrate against Control Warrior as well, but struggles against Oil Rogue and both Midrange and Control Paladin.
Of all games at Rank 5 or better, my match-ups from worst to best where I have at least 10 games:
- 30% oil rogue
- 33% ramp druid + combo
- 35% control paladin
- 44% control priest
- 50% midrange shaman
- 58% mech mage
- 64% mech shaman
- 67% control warrior
- 67% face hunter
- 67% handlock
- 76% midrange hunter
- 79% ramp druid
Oil Rogue is tough because Sap wrecks you, and Rogue is really good at removal. Its tempo gain on turn 3 with Backstab/SI:7/Poison and follow-ups with Blade Flurry/Eviscerate make it hard for Druid to stick a minion from turns 4 on. If you drop a Sylvanas or Ancient and it gets Sapped, you are basically dead. Finally, if Violet Teacher pops off tons of apprentices, you might get great Swipe value, but you are still behind on tempo. The games I tend to win are ones where I Wild Growth into Sen'jin, then Belcher/Druid of the Claw, and keep a board presence throughout the game.
Against Paladin, Equality is a nightmare for your big minions. True, you have lots of big minions, but their never ending production of small minions is a huge hassle. You never want to run your 5/10 into a 1/1, but if you don't remove Recruits, then Quartermasters destroy you. You have a LOT of trouble dealing with 3+ 3/3s. If you aren't in a significant Tempo and/or Card lead by turn 8, you are in trouble. Games I win I usually have board the whole time starting turn 4-5, which is tough given Truesilver's potential.
Combo Druid sticks minions on the board, with Piloted Shredders, Shades, and possibly Spectral Knights instead of bigger Taunt minions. You are often behind on Tempo because they have a lower mana curve, so unless you can somehow get a favorable swing, you are playing from behind, which is exactly where Combo Druid wants you. Usually I'm hoping to Wild Growth and get into my bigger minions first, but that's not atypical for any Ramp style play.
My Mech Mage match-up has improved lately, thanks to Kezan Mystic. I am pretty sure my winrate skyrockets if I can swing Chow + Wild Growth T1/T2. Still, Mage always has the potential to run you over in the beginning or close it out with an Antonidas. Ramp wants to be solidly on the board from turns 5-7 so that it can wipe Antonidas out if/when its finally played. It's often OK to take a Fireball on a Sen'jin or Sludge Belcher as long as you have an Ancient of War follow-up.
The other deck I find most annoying to deal with is Shaman. The never ending supply of minions plus Flametongues is a huge problem. Hex is just as bad if not worse than Rogue's Sap, as the tempo swing by removing your 6+ minion for 3 is often irrecoverable, not to mention Shamans are even tougher to win back board control from. Swipe is garbage against the 2-health totems.
I don't know why I do so well against both types of Hunters. I was really worried about this match-up at the start, but like against Mech Mage, Chow+Wild Growth is a great start. Predicting Hunter's play is super important. T4 Houndmaster or Shredder, T5 Belcher, T6 Highmane, T7 Boom. It gets scary. But luckily your minions match up really well. Sen'jin kills Shredder, Shredder/DoC match their Belcher, Ancient of War beats Highmane. But that means you need to be ahead on Tempo and/or have a Wild Growth. Try and remove as many Beasts as possible to weaken Houndmaster and KC. Don't forget about Freezing Traps, but also remember Snake Trap is still played. Be careful running into minions with an unknown Trap unless you have a way to deal with the Snakes, like a Swipe.
Control Warrior traditionally favors the Ramp Druid. You want to minimize the value, and perhaps more importantly, the Tempo swing the Warrior can gain from their premium removal in Shield Slam and Execute. The 2nd hit from Death's Bite clears Sen'jin, Belchers, and Lores, so be careful of playing into that. Finally, avoid a devastating Brawl and Sylvanas, and you can often pull off a win. You have more big minions than they have cards to deal with. If you get a value KT, you can also basically win.