The cloning area looks fine, as the clones will appreciate the light falloff on the sides as clones don't need something too harsh right away.
What Midzeye said about the flowering area lighting is dead on though. Thats only enough light for about half the square footage of the area you have. The height of the box, 4 feet, may compound the problem by not being up high enough to produce a good light spread if you aren't very careful about keeping the height of your plants low.
Good design though. Also, about the intake fans. If you are using a good quality fan to exhaust the growbox through carbon filters (you basically NEED a high quality exhaust fan, as simple inline fans and whatnot just dont have enough power to push through carbon filters) you really don't need intake fans, just intake vents. Save your money. Air will rush in through the vents to replace the air pushed out by the exhaust fans. The intake fans would just be redundant.
Also, when growing in such small areas, heat is always an issue. An aircooled reflector is almost a must in such designs, and it looks like with your plan it would be a sinch to add some ducting from the reflector to your exhaust, so not too big of a deal. If you don't though, I can almsot garuntee heat issues.