>>15768751. you should use "smooth" nodes on angular objects (for example look at your elbow, it looks kinda unnatural)
2. About buttons. You can use "circle tool" (F5 hotkey in inkscape)
3. I can recommend you to watch Derpy Answer's stream when available, he kinda helped me with vectoring (yay)
>>1576418REQUESTING: a vector with huge amount of frills