I just want to say that I've decided to go with.. Arduino DUE!
- 32bit ARM architecture (84Mhz clock speed / 512 KB Flash / 96kB SRAM)
- Digital I/O Pins: 54 (of which 12 provide 8bit PWM output)
- Analog Input Pins: 12 (12bit ADC)
- Analog Outputs Pins: 2 (12bit DAC)
That's plenty of high resolution analog inputs/outputs and GPIOs and (the most important thing) I've managed to connect it to my "home control" computer so I can remote read/write all those ports. The next step will be to buy a RIoTboard/BeagleBone microcomputer to swap that old "home control" PC.
Regarding my PV panels - they're doing just fine (direct charging the batteries). And it's going to run this way for a while because I just don't have time to build the MPPT charger right now. My big struggle is to build that 4kW sine inverter to complete the off-grid adventure.
PS: Thanks again, Damon.. your previous post made me decide to go with two separate boxes.