Currently, much of the additional attributes on columns are accessed via info, which helps treat mixin columns equally to regular ones. This could be taken even further, by also moving things like pprint to info, so that the way columns represent themselves in a table becomes something info is used for as well, thus making the separation of regular and mixin columns much less of a concern for Table.

@taldcroft made an initial implementation of this in #6720, which had some issues for MaskedColumn; this issue is a reminder that it would in fact be good to do this, if someone has the time to work out the kinks.