Im in the process of attempting to install drip irrigation to my blueberries. Ive only got 3 raised beds now that are 3ftx3ftx10in and 20 potted plants. Using rainwater with about 1200gallons of storage. I will be using a 1/2hp pump. Guessing about 75 drip emitters total at 1 gph each. Total lenght of pipe will be some where around 130ft of 3/4inch pvc ran in the ground. Ontop of that will be the maybe 30 ft of 3/4 poly tubing for emitters.
Questions,

Will a 1/2hp pump supply enough water to only have one zone for all the emitters?

Do I really need a back flowpreventer/air siphion if automated valves and a check valve are in place? Do I even need one with rain water???

I have no first flush diverter on my rain system so the water is pretty dirty. Any suggestions on filtration?

Any controllers and pump start relays you can recommend and ones you dont trust or have problems with?

Any problems you guys/gals have had and what you would do different if you had it to do over again?

Anything else related??? Things Im not considering here???