During my tests the arduino mini pro 3.3v and the sim800 module use a lot less power.

Currently im running them on a tiny solar panel and a bad 600mAh battery that charges up to 60% max.

So i have made a all in one pcb to make my final project.

I will use a on board solar charge controller CN3065 and a MCP1700 so i can unsolder the regulator off the arduino mini pro. This regulator is much better for this use and uses much less power.