Which do you prefer to use at your organization?

We are migrating from a multi-tenant MS365 environment to a single tenant and need to decide the best geographic location to register the new tenant. Our footprint is global, our HQ is in the UK (where IT is led with much more Microsoft experience there than other locations), and our biggest operation is in Germany (around half of the Group's employees based there), so we've narrowed the choice to UK or Germany. What should we be taking into account to make the right decision on this? Current thinking is that the biggest location by volume of users makes the most sense, which is Germany, but there are some Germany-specific 'quirks' that should also be considered (workers council etc.).