I top my plants at a little beyond where your girls are now, then start the LST a week or so later when they start to show the result (dividing so side branches become tops). I would then either give them another week and stick them into flower (for a smaller plant with a few nice fat buds) or let them veg, top again, LST some more and veg longer to get more bud sites.
I'm also a CFL closet grower, been at it since the start of this year for the same reasons as yourself (life's too short to smoke bad weed!) and have learned alot/enjoyed the experience.
My advice would be to follow your instincts, since everything is going good for you at the moment, look at how it progresses and you'll learn much about how different strains take to your situation. This first grow is a learning exercise with the bonus of some bud at the end
I would take cuttings from whichever plant is the strongest looking at present, delaying flowering for a week-ten days to let it recover, maybe also take from the second strongest. I personally never continue a genetic that looks weak.