Question: How to do the white-balancing for the RED filter?

Nice photos. I suggest using lighting conditions similar to those for the photos you plan to take. Once you get the white balance routine down it's easy enough to do the day you take photos. That said, if you use an old white balance setting with different lighting conditions I wouldn't expect that much of a difference but that would be good to test.

For the color table you can pick one that looks nice. They aren't really designed for the different colored filters since in all cases you are calculating NDVI and in principle NDVI from a red or blue filter should be similar. That's not always the case but they shouldn't be too different. If you want to compare the colored NDVI images with other images that you should use the same color table so they are easy to compare. If you want to show the images to other people it's good to include an insert or legend of the color table so people know how the low and high NDVI values are colored.The Blu2Red in the color table name just means the colors range from blue (low) to red (high).