Good afternoon, etc.
1- In regards to cactus for infinite water, seeing as how you'd need to have a decent amount of sand to sift to get those cactus seeds, implying you've probably got a cobble gen and furnace going, and I'd imagine hunger overhaul as nerfed their growth rate, pretty sure cooking dirty water will be faster. If Open Blocks sprinklers weren't disabled maybe this option could pull ahead, but at the end of the day play how you want ^^.
2- In regards to automating Pneumaticraft, once I've got my parts all set I just set the filter to the PCB's and the transistors. Granted, I didn't automate it fully on my end, but I'd just throw the ingredients in the top hopper and the stuff would pop into a chest in the bottom. I'd assume at that point you pull the PCB's to your laser set-up, the output gets put back into an AE system with the transistors and it all gets auto-crafted. I'm not entirely sure if you'd need (and I can't remember the name of them exactly), the life extending upgrades in the chamber, but hey, every little bit helps.
On a side note, remind me what SMF is? I'm drawing a blank on what you mean.