I use Canna in coco under LED. I did a couple of grows with just A+B then added the whole range in my more recent grows (A+B, rhizotonic, cannazym, p/k, boost). I use Canna's light feeding schedule. It certainly works okay but with 5 different solutions to mix every time you feed it gets boring pretty quick. It also ends up being a bit pricey keeping up with everything.
Why are you looking to change from GH? I'll admit I am considering switching in the opposite direction, or maybe trying DynaGrow, to reduce costs.
If you do move to Canna you'll use as much cannazym and boost as A+B but you'll use less rhizotonic and only a very small amount of p/k. i.e. only buy a small bottle of p/k.
I add CalMag occasionally too.
I don't really have anything to compare my canna experience to I'm afraid. I've been very happy with the quality of the weed I've grown but I'm still working on increasing yields. I can't say my buds have been gooey per se, my resin production seems pretty "standard" (i.e. seems comparable to other growers weed I've seen).