Cancer never really dies, it just goes dorment for a while. Same applies to Cubelock in HS.
So Odd Cubelock is not and never will be as strong as the original Cubelock. Just the fact you cant run Blooreaver and Umbra hurts the deck, NOT the Lackey and Pact nerf. You can get heals in other ways, and even restricting your deck to Odd doesnt hurt you. Let me explain:
If you facing some aggro deck that isnt Odd Pally you can just do some shannanigans with your Cubes Facelesses on you Rottenapplebaums, healing you massively while providing a taunt presence.
Another way to heal that people are forgetting is that you dont get hurt by Hero power, which you did at least for 8 dmg before which is exactly what you lose with Dark Pact nerf.
Odd Paladin is very common now and eats up Cubelock for breakfast specially one that hasnt Defile and Hellfire. In these match up you wanna go for Despicable Dreadlord and shannanigans with Cubes or Faceless on them and Odd Paladin cant really do anything against you.
In control matchups its easier cause you have single target removals and you can find big minions with Discover on Stonehill and Dark Possession. You have 4 chances to get Rin from these cards. Now since you dont get late game value from DK you have Elise to help you and Alex. you can literally win with Alex and next turn Doomguard and Cube Dark Pact providing you pull them from you Weapon. The weapon can return back which is a killer move against control decks
There are different options and ways to tinker with, like more or less Mortal Coil, or like Dollmaster and Sense Demons more voodoo Dolls, Lone Champion for Tar Creeper etc, but this works better than expected and it seems like the opponents get confused by your deck
Tip dont equip weapon vs control matchups until u can get just your Doomguards from it as u cant kill them by comboing with Alex, tho sometimes u can do it just because of the insane value from Dreadlords in order to get a board dominance.
Just tap away, your win condition is the Skull hence the Kobold to fetch it back