I am one of those who developed the requests for the new option paid by Wikimedia Italy. This modification, as developed, is hardly useful. For example, if I only want to see the new buildings mapped in the area, I don’t want them “drowned” together with all the highways mapped in the changeset. It is very slow to distinguish them to validate them when both buildings and highways are displayed together. Here is an example of such a changeset: https://www.openstreetmap.org/changeset/135742484.