I could have this use case not quite right, but it seems to me that if I create custom fields on board A, then I move a card from board A to board B, the custom fields from board A will now be applied to all cards on board B. That's not ideal. I'd like the fields to stay with the individual card as it moves from board to board, but if you have instances where cards from 5 different boards with 5 sets of custom fields could all be moved to 1 board, then that 1 board where all those cards from other boards ends up are going to have a ton of custom fields that don't make sense for those all of those cards, and the cards start to look overburdened with custom fields and are, therefore, harder to work with.
