Plants look great. GG are heavy feeders. I hear you with trying to weed out bad advice. I would stick with GH feed charts it's hard to go wrong with them when you already have healthy plants. http://gh.growgh.com/docs/Feedcharts/GH_FloraSeries-DTW_03216am.pdf
You can keep things simple or buy more of their supplements. You will find that you don't have to buy their full line up to grow great weed. Good plant genetics, good growing techniques, good lights and giving them what they need at the right time is key. I have followed a bunch of growers using GH and they have gotten great results. I would think about adding some cal/mag into your routine a few weeks before you go over to bloom the buds really need it to develop properly. If you want to bulk up your buds use their liquid cool bloom the extra phosphorus and potassium will add some weight to your grow just go easy with it because it's very strong. Hope this helps.👍