For making clothes you'd need a modeling app. Amapi 4.2 something is free and can be very useful. There are lots of other modeling applications at various prices. To make morphs u'd want a 3rd party 3d application that supports OBJ format well. Mimic for talking poser people in animations. Various clothing packs, models, texture packs from Renderosity or any of the many other merchants can make Poser go a LONG way. UVMapper Pro, though the freebie version does a good job. I guess it all depends on if you plan on making animations, video editing software could help. Making clothes is another area, textures another. You didn't specify your needs, so it's hard to recommend something really specific, but I've given ya some ideas. Good luck.