When boxing, consumables arent really necessary. They are just one of those kinda nice to have buffers if you want to spend the money on it. personally i prefer to either store the flowers or sell them.

But if you are so inclined to dump your money somehow, I would suggest that you go with superior wizard oil, adept's elixir and either mageblood elixir or draenic wisdom.

Or cut it all short and pop elixir or blinding light.

Also, the only consumables I use on a regular basis on my shamans are mana potions. I carry 3 stacks of mana injectors on each of my shaman and I am always popping them whenever i need the mana. It helps that i also made all my shamans alchemists and they all have sso alchemy stones, but meh~ I just lost mana potions.