I need to know how much ias i need for my baba to reach 5-4fps per throw. With weapon speed of -20,0 and 10. Somone know this?

Also suggestions of stats, skill points and gear would be appreciated.
I have gear and stats,skills in mind but i wanna see other ppl's suggestions.

Plz tell me i did the right thing by maxing double swing to enhance double throws dmg.