I'm a fan of the silicon. As it raises the pH, it goes well with ro water, I use it instead of regular pH up and continue with my 'no additives' mantra.

For accelerated learning, a staggered harvest is difficult to beat. Assuming you have a separate veg area I'd be playing with the 12/12 timer until the strain finished at exactly 9 weeks and do them in batches, one light per batch and a harvest every 3 weeks. That's 17 harvests a year. Do something a little different every other batch and you've got 8 or 9 sets of
valid results every year. The difference a staggered harvest has made to my 'tweaking' is night and day.
Doobz is having a great grow using what seems to be a 'lucas fomula for coco' mix of 2 parts GH micro to 3 parts GH bloom.