How can this topology be improved? Multiple attempts and several hours later, I have failed to create a successful all-quad mesh again. I keep trying to visualize face loops that define the edges I need on this object (a screw), but it is very difficult to join these dissimilar sections of geometry together. I have been watching tutorials/speed modelling sessions in an attempt to gain some further insight.
I am guessing that the round part needs to be spherical-ish, because if the verts are not distributed evenly, then it will appear lumpy instead of round/smooth...though clearly, the perimeter loop where the plus shaped area meets the round part has not-evenly-distributed verts all along that edge...
I tried to join the two edges and redistribute the verts to make them spherical, but it looks terrible. Here was that attempt (notice that the ridge is wavy and uneven...), I abandoned this approach after it seemed to be a lost cause:
And here is a later attempt, the round part is a bit lumpy/not-smooth...I also realized that there was a triangle here later on too (how would someone fix that? start completely over, since adding geometry would change the number of verts at the joining edge between the two surfaces?):