Pretty good shots, considering the very low light conditions. I used to have similar issues with strange color casts when shooting theatrical performances, which also make heavy use of all sorts of colored filters. Then I began to experiment with the Kelvin scale in the White Balance setting. If you shoot in a concert setting again, I recommend experimenting with the Kelvin scale and it might correct a lot of the color cast. To do so, access the White Balance setting and scroll down to the "K Choose color temp" setting. The highest setting is 10000 K and the lowest setting is 2500 K. Generally speaking, the lower the setting the better for theatrical and concert lighting. I recently photographed a play and the pix had odd color casts until I lowered the White Balance all the way down to 2500 on the K scale, then the pix looked very natural. Also, some of your concert pix appear to have some blown highlights, which perhaps could have been avoided if you had lowered the exposure compensation to -0.7 or perhaps even -0.1. I've noticed the D700 tends to overexpose and many are recommending setting the exposure compensation to -0.3 by default.