Thanks for contributing to our forum.
I certainly understand how it may be beneficial to enable the "Enable Optional eBay Gallery Images" option by default, but we actually have a number of users who place images within the "Auctiva Image Selection" area that they do not wish to include as Gallery Images and doing so could be problematic for these sellers.
I have forwarded your comments in this regard to our Product Management team for consideration though. Perhaps we could provide an account preference that would allow individual sellers the option to enable this setting by default for their accounts or something similar.
We appreciate the feedback!