if plants are being fed proper nutrients in DWC systems, they are intaking enough food to build stable branches and do not require the use of trellis systems. With true sativas a support system might be needed in DWC, but im sure that if the branches were trained during the veg cycle to be thicker via LST'ing, it would solve the problem.
kritical, its cool to keep the humidity at 60, but you are potentially risking bud rot at anything above %50. If you want to reduce this risk, just make sure to put another fan in there to circulate all the air and avoid dead spots in the room that only 1-2 fans can create. This will ensure all the flowers are aerated avoiding the rot. glad to see the ppm counts are up :) and other than the pH a tiny high, looking sexy.
hopefully her stretchiness in the main cola will fill out (9 weeks is a decent flowering time and allows for things to work themselves out)
have you been bending back any of the branches to allow light in to lower branches? Also, have you trimmed away any leaves? (Hesitate when doing so... the solar panel leaves (big fan leaves) do not come back readily and your flowers will suffer in size if you cut them)
good job