Canna is a good product, I don't use it cause its too expensive and I have been using GH for some time now and only reason I steer away from GH is because the local shop gives me new stuff to trial for feedback.
Don't over think it, its not really that hard to keep things on a very simple level, then slowly add to your attack. Additives do work for the most part, but some more than others and others don't make a dramatic difference at all. The thing with additives is that the marketing department will throw some fancy label on it and make public claims that it will increase your yields by up to 10-20%...ignore that shit, the marketing department gets a % cut of the sales, so of course they are gonna feed you a load of shit to get you to buy it. AN is the worst at marketing traps, don't get me wrong AN does work and it works well, but the labels and names on the bottles are a part of their marketing lurer. Additives more or less help, accelerate, or assist your base nutrients to some degree, they don't actually make your plant bigger that is pretty much the job of N-P-K
So, yes you can grow some really nice buds on just base nutrients alone. I personally only use CalMag, Superthrive, Diamond Nectar (for a Humic Acid), Molassas if I grow in coco or Flora Nectar if I am DWC....so these things at the appropriate stages and the GH flora 3 part series as base nutrients.......I will say I am about to use GH Rapidstart as I got given a bottle for a trial