You sound like you got it down. I wouldn't add anything else. I would save a bit by not changing rez untill I topped up with 15 gallons of water or 2 weeks whitch ever comes first. I might go up on cal-max if I see any signs of defisncies.

You need to measure your nute PPM's first to bring to the strenth you want and then add additives.

Only thing else you need to add is love.