Hi Pizpot
Nice greenhouse, I'd love to use mine but have a nosy neibough problem.
I like to add molasses in the bloom phase i generally use blackstrap molasses made from sugar cane.
If you are using BioBizz Grow you don't need to add molasses as one of its constiuant part is organic sugar beet molasses.
Using baby bio is ok in the short term as it is better to have your girls not going hungry and getting N def, although you already know BioBizz is gonna totally sort them out.
I agree with Blue on the top dressing with guano to easy to go over the top with ferts. Guano is powerful stuff especially if you are already following the prescrided doseage of BioBizz.
I have seen some awesome grows using Subcool's supersoil which have gone full grow using nothing more than water (large pots were used)
Using light mix and and fert is also ok as you already know, but think if you can buy or make super soil it would be a the prefferable way to go.
Here's how to make sub cools super soil -
http://www.hightimes.com/read/subcools-super-soil-step-step
I would also say add some mycorhhizal root inoculant , it seriously gives you plant a boost by creating a secondary sybiotic root system of fungal hyphae.
Here a little read about what mycorrhizae can do to benefit your plant -
http://mycorrhizalsymbiotics.com/content/benefits-mycorrhizae
I'll be sure to keep followin your grow, looking forward to future post.
Peace
Growerz