This is a good question.
My answer is Medicham, but I want to say the reasons.
First, I searched all the pokemons in the "human-like eggs group", because they are the most compatible with us humans (obviously).
After I saw all the pokemon with a cute, humanoid design (Lopunny and Lucario are cute, but they are more "furry-style").
Futhermore, no gijinka, anthro or kinda... the pokemon must be in her "real form", like we see in the games
Finally, I read the pokedex's description, to search the better personality, behaviour and features.
So, I chose between Medicham and Gothitelle . Gothitelle is cute, beautiful and could be a good choice, but I found that pokedex's voice "she could read her trainer's lifespan" a little sad and I didn't want to hurt anyone, so Medicham.
IMHO, it's a very good choice.
