It would be great if Candle or Lotharek could help with this, as this has been an ongoing issue, for literally years. I'll admit that I was disappointed after spending the money, where none of this was really mentioned in the "marketing" of the VBXE. I know that many are just "meh it's not a big deal" with this, but when I can see the clear difference between the color scheme in UAV, and the VBXE output, especially in games, this is really an unsatisfactory solution for people who grew up and are used to NTSC on the Atari. Since I have no idea how to change it, there is little I can do (I can't even return it now), but voice my opinion, but it seems that since the palette can be programmatically swapped out, that creating a new NTSC core would be relatively simple.
As stated before, it is basically useless to have a program to swap out the palette, when it gets cleared when the power is cycled, which is essentially required for most games, especially when running from a cartridge. I kind of put my Atari stuff on the backburner for now, as I had other stuff to work on, and this whole thing just put a bad taste in my mouth about getting a modern video output, after also having issues with Sophia, which in the end I should have just bought a DVI monitor that worked with it, but VBXE seemed to be the solution for everything, only finding out after the fact about the palette issue when the output colors did not match my previous experience.
The fact that this gets brought up again and again, with no resolution from the creators/sellers, is disappointing to say the least. I spent many hours chasing this down as an RGB to VGA converter issue, when it was the palette all along. That no one seems to care, except those of us with the issue, is extremely frustrating.
As for consensus on the palette, again I have no specific knowledge, but it would seem that there are NTSC palettes for other systems that worked, or that are used in Altirra. Having done a little bit of research, I was unable to find definitive information on the NTSC palette, so I must have a lack of knowledge on the subject that I can only suggest what I have.