Air-cool the hoods... ~$100-150 per hood, you'll make it up on your first harvest, 'econo cool' hood works fine... 6" active exhaust on the hoods themselves.

You can do 2 in line. You CAN do an isolated circuit drawing air from somewhere else, and then exhausting it into yet ANOTHER location... but then you have to add yet another hole... I run my air cooled 1k open at the intake end and it serves also to exhaust used air... it exhausts to another room.

Intakes... Yeah I hate to say but adding another 6 inch hole somewhere, preferably LOW (floor) with a duct booster fan is desirable, and add a booster fan to your existing intake. I have found that passive intakes simply don't cut it when you bring out the big guns. I draw my makeup air from a room with an a/c runnin 24h set to a LOW temperature.

Catch the pwnage of the Braves last night? wOOt.