We're probably using different translations :P
vector layer to me is the new layer icon with a pen on it. Guess it must be line art to you. Smoothing is on top of the workspace, the farthest right in the lower menu thing.
Ahhhhh SAI. your translations are so confusing. Especially when half of the stuff is in Japanese.
Okay. So vector is linework for me and stabilizer (which I'm guessing would be that drop down menu that goes from 0 - 15 and then S1-S7 or so) is smoothing. So even with those my lines are great but I guess I should just be more patient about it until my tablet pen arrives haha.