I'll answer them in the order they were asked.

You should keep your plants in veg until they are between 1/2 and 3/4 as tall as you want them to be when finished. for example, if you want a 3' plant at harvest, you should veg it until its about 2' tall.

I wouldn't expect them to get too big, since you're vegging with CFL's. (you are using daylight CFL's, right?) However, the HPS should bulk them up a bit in flowering. Another option is to use the HPS now. Personally, if it were between CFLs and HPS, I'd use HPS all the way.

The yield depends entirely on how big you grow them and how well you grow them. you can grow a super high yielding strain under a 1000w HPS, but if you don't feed it right, water it correctly, or adjust the Ph accordingly, It won't flourish. There are also methods you can use to train your plant and increase yield.

Yes, the taller/bushier they get, the more bud the plants are capable of producing. However, CFLs will not allow your plants to get very large.

Vegetative- can take anywhere from 3 to about 7 or 8 weeks.
Flowering- can take from 7 to 12 weeks, depending on strain.
Drying- 1 to 2 weeks, depending on drying conditions.
Curing- basically as long as you want, but 2 to 3 weeks would be okay.

So I would expect your entire grow to take approx. 16-18 weeks, but again, this is all dependent on how well you take care of your plants.

A few more tips.
-Watch your watering. you should only do it approx. every 3 days.
-Make sure there is plenty of drainage such as perlite in your soil (If you are growing soil)
-In soil, don't worry about feeding your plants any nutes until they are a little bigger.

That should give you a decent start on your growing endeavor. Good luck and Happy growing. :jointsmile: