OK, let's see:
1: Naughty Nature
You would have a 100% chance of passing down the Naughty Nature, because the Male one(with a Naughty Nature) is holding the Evertsone. Ludicobro is wrong in saying that only the Female can pass the Nature down. I believe that only held in Gen V.
2: Speed Boost
There is no chance of you getting the Speed Boost Ability because males pass down Hidden Abilities when bred with a Ditto. If the Female had Speed Boost, you would have an 80% chance of the Speed Boost Ability.
TL;DR, you won't get a single offspring with Speed Boost
3: Decent IVs
Female Carvanha: 3IVs Perfect
The chances can vary from a 0IV baby, to a 4IV baby, but you would mostly get 1-2 IV babies. I can't give the exact chances, because I'm only in the 7th Standard, but when you get a 4 IV baby, start breeding with that instead.