When creating such blends I find that using a [blend along a curve], is a better method as it allows you far greater control as you can [edit the distance between steps] giving you smoother lines. (The 'curve' can also be a straight line).

I usually create these with [bevels] so that it finishes up with 3D lighting. The blend step spacing is even more important with this method as it needs to correspond with the bevel size and shape.