Im thinking that the lankiness is due to the aluminum foil distorting the lightwaves as they reflect off it. I use mylar, but flat-white paint is WAY better than foil. %There is titanium white semi-gloss that is like 70% reflective, but mylar is 95%+. Looks like shes pretty healthy. I got 4 ounces off of a Blueberry plant of similar size. However there are FAR too many factors to even speculate how much you might get, mainly genetics. Example: I am SOGing lollipop colas and a typical Blueberry(DJ Shorts) yields about 21 grams dry weight on average; my OG Kush(Tahoe), however are yielding closer to 14 grams dry weight under the EXACT same conditions. which brings me to the next factor: environment; how much light does she get? soil or hydro? feeding schedule, temperature, rh, how much love do you give her? Are you running CO2? Hell, mine usually pack on about 20% of their weight in the last 2 weeks, so pulling early or late is a big factor, too. Keep up the good work and invest in a jewelers loop, pocket microscope or traditional microscope with a good down-light so you don't have to guess when shes ready to harvest. Good Luck!