You are over complicating the fun of building. if you are using mt2206 2200 motors a 6 inch prop of around 4" pitch and a 25 or 30 amp esc will be fine.probably go for a 4000mah as its a little lighter. the most flight time ive ever had is 19 mins and that was over discharging the battery, and flying relatively slowly.
15 18 mins would seem good.
bigger battery more power used to keep heavy quad in air. smaller battery less weight but less mah to use.