Cannabis flowers can take anywhere between 6 and 16+ weeks to mature, so you still have a long way to go, with the majority of white pistils being exactly normal for this age/stage of flowering.
Hang in there and try not to get too impatient, it will happen, just not overnight!
After looking at your diary, I would say you have another 4-6 weeks to go before harvest maturity.
Also, try and not do any further defoliation of healthy green leaves, this will just reduce the capacity for your plant to make energy, thereby slowing growth and maturity.
You should however, remove any brown/dead leaves from your grow space, these are prime targets for mould and fungus to attack, and this is the last thing you want during flowering!
Hope this helps,..........
Organoman.