I laud the attempt and I think it's important there are more projects that try to compete with their American counterparts. I do want to gently note that if your entire pitch is "we are a bold, independent European alternative that liberates you from the hegemony of the established American players," maybe don't name your product the exact same thing as the product you're replacing? "Office." They named it "Office."
More seriously, Office is a great word for what the software package does, and it can't be trademarked. You can have Microsoft Office, Libre Office, and Europa Office.