Hold on guys lol, your asking a lot of questions that I as a newb can't answer. I've been growing outdoors for a long time but a bit of a newb indoors. All I can do is relay a bit of my own experience. As for veg times I typically veg for 25-30 days because I run into height problems but that's strain dependant. If I run, for instance White Russian, I get into trouble and need to supercrop the shit out of them. My last run of God bud was fine. Check the strain out and read some diaries if out there, that will give you a clue. 9 plants in a 3x3 area is gonna be packed so you won't have much room. SOG grows typically are lots of smallish one bud plants, like a 4x6 tray filled to the max. I grow using low pressure sprayers in deeper covered trays with 6 plants in each setup and flowering room is 4x4 and again strain dependant it gets real busy as well with 6, I really don't go by size before flipping as much as time, but usually they have 4-5 true nodes, top once, let them recover then flip and pray lol. I'm fighting an epic battle of root rot right now so don't feel very knowledgable, grow is going to shit lol.