Twinsies is hard, but you can at least work toward it. I will complain that theres no way to check if 2 wolfs can breed, making the flea market more of a gamble than it should be.
The one for the gauntlet where you need 2 matching companions- have the devs done that math on that? I haven't even gotten one yet. It feels impossible and there's nothing you can do to work toward it, it's in the hands of the rng. Extremely not fun to see that achievement stagnate.
I'd probably add an achievement for fully leveling wolves. I figure something like that might be introduced later once the level cap hits it max.