I have been experimenting a bit with how much red to add and I found its very important to get at least a minimum amount of red to spur the corals into growth. I typically went with a very blue look almost like yours rbja, but the growth was slow. Algae was nicely kept in check though.
My girlfriend expressed that she liked it brighter and whiter and so I started adding more whites to the mix and the growth picked up. The whitest mix I went with was:
Super Blue
Fiji purple
B+
KZ New Gen
Aquablue Special
KZ New Gen
KZ new gen
Super blue
Colors looked really good, especially reds, but then some of the blue colors started to fade a bit and there was a little browning. I have arrived at the following mix and the color is great with excellent growth:
KZ Super blue
KZ Fiji Purple
KZ Super blue
KZ New Generation
KZ New Generation
KZ Super blue
KZ New Generation
Super Blue
I find that the New Generation gives you a very cool white look but there is plenty of red in the spectrum, if you are down to that few of tubes Id give it a try. When I add a coral plus it is too much red, and when I add a Aquablue Special its too much green and the colors take a hit.
Reefgeek has a very cool chart of bulb mixes that will also give you some ideas, they have this rough equivalence:
Blue Bulbs = ATI Blue Plus / KZ Superblue / Giesemann Actinic Plus
Purple Bulbs = ATI Purple Plus / KZ Fiji Purple / Giesemann Aqua Pink
Bluish White with a touch of red = ATI Coral Plus / KZ New Gen 14,000K / Giesemann Lagoon Blue
~10-12K white = ATI Aqua Blue Special / KZ Coral Light 10,000K / Giesemann Aquablue Plus
I have all these bulbs except the 10K coral Light and I find that the crispest white bulb is definitely the KZ New Gen.
Here is what the tank looks like with my current mix(a tiny bit bluer than reality because of the camera):