So, I'm trying to flesh out a bit of my placeholder art for Forklift, and in doing so give the tank more directions than "left" and "right".


Ok, so far so good. Now, I've been trying to make a version of it rotated 90 degrees to face downwards...


...and I keep coming up with abominations like this. These things just don't look right, no matter how I do them, and I feel that in a sense clinging to normal ideas of perspective is unhelpful. On the other hand, I'm not an artist, so I'm probably verbalising from my posterior.
So, any advice on how to improve the up-down kinds of view? How wide do you think the tank/turret ought to be from the front?


Ok, so far so good. Now, I've been trying to make a version of it rotated 90 degrees to face downwards...


...and I keep coming up with abominations like this. These things just don't look right, no matter how I do them, and I feel that in a sense clinging to normal ideas of perspective is unhelpful. On the other hand, I'm not an artist, so I'm probably verbalising from my posterior.
So, any advice on how to improve the up-down kinds of view? How wide do you think the tank/turret ought to be from the front?