Help with grow room choices! (:

[Episodegrow]

I need some help making some decisions about my grow room/tent. I'm just a simple hobby grower I've been growing for maybe half a year with soil/hydroponics now. I currently have a 4x4 tent with tomatoes, cucumbers and peppers growing inside. I'm using a 400w mh atm with a day time temp of 79, nighttime of about 70 and humidity of 60 and 40 for day and night on a 18/6. (And it's dwc)

Now my question is..: my cucumbers are doing amazing, my peppers are growing slowly but I'm not sure if it's too slow. My tomatoes are doing so so but I've noticed some flowers fall of. Could this be too high heat? I do keep the 400w relatively close but there no sign of leaf burn.

Secondly I have a cool tube with a fan going through. I was thinking I'd rather get a hexagon shaped reflector as the cool tube reflection isn't ideal. This would increase the room temp but at the moment I actually don't have a fan running inside the room. Is it important to have air hitting the leaves? Should I switch to the parabolic and have more circulation or keep the cool tube and get a small fan inside?

[CharlieBear]

I am wondering about the night time temps it seems higher than needed. I am curious about you humidity choices, as humidity is often a problem for tomatoes, blight etc. Also, I am wondering do you have a fan running to create "wind" so the tomatoes will set.