I think DISC has been very useful. It is validated / unbiased and people view it as offering very basic critical insights to increase self-awareness, improve communication and support team-building. We introduced it across our organization and found that team supervisors were seeking to delve deeper with a Team-Building session around the results. There is a phrase "know your audience". Well, I apply it here, it helps people understand the way they communicate and how it is received, and in a group setting when DISC styles are shared, you're able to understand a little more about your colleague to better communicate for each audience.
Another resource that is very useful is Intercultural Development Inventory (IDI) which is used to guide individuals, teams and organizations on their intercultural development journeys. While culture is typically defined by national and/or racial and ethnic boundaries, the IDI, recognizes that it may also include region, gender, sexual orientation, ability, religion, etc. IDI terms "my culture" as the culture group to which I feel I belong the most. IDI terms "people from different cultures" as groups to which I do NOT feel I belong. I am a Qualified Administrator (QA) for the IDI.