Starting St-rr build

Well ive been doing alot of research and im ready to start!!!
Here is my package but got questions about it
1. CC MMM 2200kv combo
2. What pinnion if im running a 50 spur gear?
3. Should i go with 2x 7.4v 6000mah 30c saddle packs or 2 zippy 5000mah 4s 25 or 30c or a 5s setup?
4. Lmk know guyys...20 to 30min mains i will be doing(most likely 20)