I can't say if they want it, you can make a issue/fr on https://github.com/umbraco/Umbraco-CMS/issues and see if they are open to it, then you could make a PR about it. A lot of other people are using the Contentment plugin. This has the option of adding (amongst many other features) a DataList datatype consisting of a Dropdown with your own key/value https://github.com/leekelleher/umbraco-contentment/blob/develop/docs/editors/data-list.md