Hi Manuel, this is quite a big post, hope you don't mind...
Most of the items described by the OP is quite vague, a person can't really get any concrete requirements out of them, but I think I will talk about general issues and desired features for the torso mesh. I think the masculine variation of the mesh is fine, but unfortunately the female variation of the torso mesh is plagued with masculine features that ruins the mesh a bit. I'll base my discussion on the diagram I created below, and I've also included two example photos that show the same items on real people:
http://img576.imageshack.us/i/wishlistn.jpg/http://img135.imageshack.us/i/example1p.jpg/http://img687.imageshack.us/i/example2j.jpg/Due to the NSFW nature of the images, I have decided to link to them instead of doing an in-forum post of them. I'll discuss each item based on the color I used on my diagram and photo examples.
BLACK:
The most concrete feature request the OP mentions in his post is that the breasts start too low on the body, this varies from person to person, but I agree, they do start bulging very low on the mesh. I think we need a target that raises the entire breast portion of the mesh so that they basically start bulging just below the arm on its highest setting. Another way this might be implemented would be to add something similar to the "Nape to waist" & "Waist to hip" measurement feature, but make it for the upper breast to the arm. See my diagram (Ideally, we should be able to compress the geometry to shift the entire breast mesh up to close the gap between the two black lines).
PINK:
Due to the topology of the mesh, I'm not sure we can really address everything I wish we could, but in favor of making the female mesh more feminine, I hope we can get a target or soemthing else to fix this one: On a female the rib cage comes down at a much sharper, more acute angle than it does on a male, they also go lower down the body when compared to a male rib cage. To me, the female rib cage looks quite masculine and doesn't really come down at the correct angle. The pink line indicates roughly where I would expect the rib cage to run, but it may be best to refer to the included photos.
GREEN:
Usually, females have a bit of a fatty layer next to and below the navel area, raising that area around the navel in a circular arc. If you look at photo example 1, even when a fit female is stretching back, the area around the navel is still quite fleshy. Example 2 shows this as well. In the female mesh variation in makehuman, the mesh curves inward next to the navel area which doesn't look right. I think the entire area around the navel should be revised for the female mesh to look more feminine, with the circular arc below and around the sides of the belly button. There could be a mopth target to increase/decrease the depth of the fatty layer, but it probably wouldn't apply to the male mesh.
BLUE:
This one could be a morph target: Fit females tend to have a prominent line running down to their belly button, occasionly it will also continue below the belly button and may even extend over the rib cage as well (see the included photos to see what I am referring to). This detail is in the current mesh, but it should be an option to shift it deeper into the mesh to make it more prominent.
WHITE:
In my diagram, on the white line, you usually see quite a strong change of angle and the rest of the area runs a bit lower on the right hand side. This is best seen in example photo 1. In the female mesh, it looks like this feature was attempted, but it is too subtle and possibly not in the correct place.
Also, there is a buldge (another rib cage issue?) between the breasts that is slightly too high, it should be brought in a bit so it doesn't stick out as much.
BLACK is probaly number 1 on my wish-list. Followed by getting the female torso looking more feminine, starting with PINK and GREEN. Some of these could be morph targets, BLACK most certainly should be its own morph target. I also think there should be a single "female curves" morph target that makes some feminine features like WHITE stand out more. I think for GREEN, the belly button area should be revised, the topology is a little difficult to work with in that area, but given how difficult it is to fix that, I think the vertices should be shifted around so it forms more of a circular pattern around the belly button, and the depths should be tweaked so that the fleshy area sticks out in the female variation instead of sinking in like it would on the masculine version.
Regards,
Raz.