You're making a crimp not a sculpture. There isn't a lug nor a crimper made that is going to offer a precise hexagon. For crying out loud a three hundred dollar Thomas & Bettes crimper jabs a point into one side of the terminal then squishes everything into an inverted U.
A correct crimp is a DOUBLE crimp. When correctly crimped, the lug should not be able to be bent where it joins the wire. It should be STIFF. The wire.
Copper like most metals does not like to be reshaped more than twice. It's OK to make a trial crimp then adjust, but continuous multiple squeezes are needless. This is why I highly recommend a 16 ton crimper over an 8 ton. For large cables.
By trial a hard wire crimp with no substantial amount of material squished out at the die juncture is perfect. Go pop a brewskie.