DIY LED Placement Feedback?

[Enigma]

I was thinking about sliding the outside rows in. I have the room to get them closer. Not only would that cluster the LEDs better, it may allow me to add even more in the future. These will be hooked up to an Apex, so I should be able to swing a good acclimation program.

Should I've the red farther to the back in the middle column? I could move it back (up) one spot, or into the last (top) spot.