Yes because if it's the bottom half I get powerful legs and if it's the top half I can always join a metal band

Of course

Goat head, I can eat tin cans and garbage

Goat legs, I can get a job climbing mountains

Can't I just be transformed entirely into a goat?

can the transformation be heterogeneous? like I could get a goat arm, goat leg, goat liver instead of just my lower half or upper half getting transformed?

if so, yes. if not, also yes.

idk probably not because being vertically half goated sounds inconvenient

imagine you say yes and it's your left half