I'm no expert so take my statements with a large grain of salt. There is no real "standard" map size, even for a particular figure, though something like the templates Daz provides might form a popular standard. Beyond that though, it's pretty much up to the person making them. You can create whatever size you want in UVMapper. You can also create separate maps for areas that you want to detail more like lips or buttons for instance. That way, you don't have to create a huge face map just to have hi-rez lips. How big is big enough? What I've heard is that the map size should roughly match the final rendered image size. This make sense to me. That is to say, for a portrait where the face is going to take up most of a 1024x768 image then a 1200x1200 face map would be good. The same map would be overkill for a image where the face of the figure is only going to be around 200x200 pixels. In the latter case, you could easily afford to resize the face map down and save memory. Now obviously, if that is the case then a lot of these 3000x3000 type maps are way more than is needed for the typical render (print I don't know about). Maybe the idea is to make it large enough that features like eyes, lips, nipples, etc. are big enough. It would seem to me to be better to give those features their own appropriately sized maps but maybe I'm missing something. When you're talking about seams/seamless, are you talking about just a border around the whole texture or are you talking about seamless patterns? Getting things to match up across seams like a tattoo that wraps around the body is apparently difficult no matter how you do it. If you do a search in free-stuff for SnowSultan, he has a lot of templates that are colored to help in seam matching. AFAIK, the vast majority of people use a bitmap editor to do textures. Whether that's because there's an inherent difficulty with vector apps or limitations on what you can do or simply popularity I don't know.

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