So as I think about it more, I'm thinking I may not do the scrog this time. It seems like i'd really be limiting the amount of usable space in this closet, and i wouldn't be able to grow as many peppers as I want. The tomatoes in the scrog would start to grow right over the tops of the peppers which wouldn't be good. The scrog will still be great if i decide to do indeterminate tomatoes later, but for this grow, i'll stick with all peppers and smaller varieties of tomatoes that should only grow 2-3 feet tall, to stay in line with the average height of the pepper plants.
Here's a pic of the layout I was thinking of using for the buckets:
Two rows of buckets fit in there PERFECTLY, but just by a fraction of an inch. I can slide the closet doors shut without them hitting the buckets.
For the fan, I was thinking of mounting a large 16" fan to the wall above the light, turning it on high, and letting it circulate within the closet. I think this should still provide some nice air flow to all the plants even though the fan would be above the light.