I prefer Kato brand to Premo - it is a bit stiffer, and I feel that, when baked long and hot, it is stronger.
If you are doing more sculpture than jewelry, you might want to look at prosculpt: http://store.artdolls.com/category/prosculpt/
It comes in only a few flesh colors, but I understand it is the preferred clay for sculpture.
Baking longer (and depending on the brand, hotter) DOES matter. Longer baking times give better strength. Many websites/youtube videos will say "bake 10 minutes" but they're WRONG. Bake for 30-45 minutes or longer. I usually do my final cure on any piece for 1 hour.
Conditioning is also important. Blend the clay in your hands or pasta machine until completely soft, flexible and warm. If that makes it too soft/warm to work with, set it down and let it cool. Don't stint on conditioning. It redistributes all the raw materials, leaving the clay at maximum smoothness and strength.
You can use many of your painting skills with clay. Learn to color your clay surface with chalks and mica powders. They're wonderful! Also, you can paint clay - I prefer to use genesis heat-set paints; they work a lot like oils, but only cure at polymer baking temps. Wonderful for antiquing and staining.
Alcohol before baking, on a paper towel or baby wipe can remove many imperfections; so can rubbing with a bit of cornstarch. Afterwards, sanding is the best way to remove subtle imperfections and flaws.