Gardenman: Good luck man sounds good, definitely get a HPS if you can the quality will be fantastic. The only problem is heat so make sure you have plenty of fans or exhaust!
Gypsion: I dont know about increasing chances of females. Everywhere i have read whether its books tutorials or people on here they all say 18/6 or 24/0 for veg. 15/9 will slow down their growth some what and may cause them begin flowering too early or cause complications? I could be wrong entirely but id stick with at least 18/6 to try and avoid hermies.