Stick with just the Flores and rhizo to be safe, pk is too hot and boost is a rip off.
Also wait till there is almost no hairs left to get the fattest hardest buds.
crap old soil, sitting around for a year that gave you the gnats. reduce watering and back off the feeding for a few weeks. Next time use coco or soil that is fresh.
Needs repotting now to reduce the leaf yellowing/drop ,it would be rootbound and stressing and nneding to take up more K.
Only watering for the first week after re potting.
Try canna terra coco and nutes next time and plan to have it in a bigger pot by this stage.