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My comments were in no way meant as a criticism of your UV map. As far as my very limited knowledge of such things goes, I think you have done a great job. I just thought that a separate material might be a good idea, but as you pointed out, it is not needed.

Thank you much, and I didn't take it as criticism at all, I was just explaining it to you. ;-)
At any rate, any and all criticism is fine with me. I may defend certain decisions, but the problem with the idea is there's no "right" way to do it, aside from a few certain rules such as no overlaps on individual islands, try to limit distortion and all that.
The problem with UV mapping and textures is I don't think it was really designed for the way it's used in Poser and expected to be able to be used by the masses. Ideally, you would be creating a figure for your game or movie, or whatever and be part of a team of developers. Someone would model it, someone would texture it, someone would animate it, someone would code it into your game and any number of other things, but your figure or creature or objects would be your team's, for your team's project, and be designed around the needs of the project. In all respects it would have to conform to a set of pre-defined specifications laid out by your project manager or client.
So, everybody working on it would know what was what and why it was as it was. The topography would be designed to make the riggers and animators happy and productive, and the same goes for all other aspects, such as the UV mapping.
You may use that figure again later on down the line, but chances are you won't and your game or movie sequel will have features better designed to take advantage of the latest technology.

Not so in the Poserverse, where the same figure will be used by hundreds, thousands, maybe even millions of of people with widely varying ideas on what should be what and how this, that or the other thing should be done. And the UV mapping is something that gets thought about and variably praised and cussed alike, as people try to texture the models. I don't think anybody who paints or makes textures for Poser models likes all the UV mapping on any one figure, and it will always be that way because you can't get a consensus from that many people. So you're designing blind for an enormous user base, each individual with his own needs and ideas, as opposed to a small team that has agreed to operate within a given set of pre-defined standards that have to be met before production even begins.

So you go with what you know and hope for the best. ;-)

BTW, I didn't point out that a separate material is not needed. There are benefits to doing it all with separate materials assigned here or there. I have a number of versions of various DAZ figures through the years that I made whole new OBJs for, particularly for consolidation of some of the materials into one. For example, all that "skinArm", "skinShoulder", "skin3rdpolygonfromthetop" nonsense irritates the hell out of me. And in a few cases I added material zones if I thought I needed to for certain situations.
So again, that's another choice thing, but what I pointed out is remapping the figure isn't necessarily necessary in order to have new material zones. However, if the desired new material zones cross over a seam, remapping may be necessary, depending on the circumstances of the UV map.
That affects Poser more than anything though, since Poser has made the (very bad) habit of overlapping UVs acceptable, since Poser before version 5 couldn't do regions. If you're using multiple regions, you don't have those restrictions, though it might make texturing more difficult.

For example, in the screengrab above, the pubic region and the body are the same UV map, in that they don't overlap. As it is now, in Antonia 116B, that is the skin_BODY material. You could separate those islands into  two separate material groups, or even give every polygon its own material group if you wanted, with no need to remap it.
And the same goes with Vicky 4 and all her different materials for the limbs, skinArm, skinShoulder, skinHand, skinFoot, skinLeg and so on: Since they're all part of the same non-overlapping UVs, you can make one material and call it "skin_Limbs" (which is what I did), and all will be well.
However, you cannot cross the leg or shoulder lines with materials, because then you're into the skinTorso mapping, and running into overlapping. You can physically assign a new material, but it will cause a lot of problems when texturing.

Short explanation is, the words "materials" and mapping" are not synonymous or necessarily  mutually exclusive. ;-)