I want to add that my edit was under the assumption you weren't actually attempting to draw it in 'correct' perspective, and were just trying to give enough of an illusion of perspective to help it fit in with tiles. But your more recent edits lead me to believe you don't want it to be overly symbolic.
You can approach this different ways, but let's look at the Breath of Fire series.

Here you can see they didn't bother at all. It works, because it's symbolic. Most RPGs of this era did the same thing. Faces are directly facing the camera, feet are staggered on top of a shadow to give the illusion they belong in a world drawn from a birds eye view. You do not see the curvature of the waist, the top of the head, nothing. It's as if they're all standing on a very steep incline.

Breath of Fire IV is a beautiful game. A lot of background elements in this game are actually 3d models. So it makes sense they would attempt to project the sprites as if they were 3D. You see the tops of the heads, the tops of the shoulders, and as Ambivorous noted, you give the tops of objects more space and the fronts of them less.
So which direction are you aiming for, Digivoxel?
@Night: I really enjoy that edit. It also highlights that Digivoxel's sprite's face and huge forehead are keeping it in musclebaby territory.