What inspired this wish list request? When first loading a messy file, e.g. a log file, often the columns all end up as "character" type because there are some text-lines inserted into the data. After removing them, the next step is to configure all of the numeric columns' data and modeling types. Doing this with Standardize Attributes takes a lot of mouse clicks, but the new Columns Manager is a much more intuitive interface for making these types of corrections.
What is the improvement you would like to see? CM, however, doesn't allow you to select multiple rows and change the data or modeling types -- as soon as you try to click the drop-down arrow, it deselects all other rows. So this request is to allow changing data and modeling types on multiple selected rows within Columns Manager with a single change on any of the rows.
Why is this idea important? It makes the intuitive action possible.