We have to be careful to not develop this into a dedicated marketing / recruitment event (which is not to say that it has no place, but it should not be the determining emphasis). Otherwise, those who are not engaged with such activities might be lost.
The great advantage of face-to-face-meetings is that people engage in a more casual and intuitive manner rather than (in the extreme case) typing on keyboards. This offers many opportunities for innovation and collaboration but also identifies opportunities that might remain hidden in digital meetings. We should exploit that, and I am not sure if adding video conferencing as a default means can jeopardize that: in such hybrid meetings, people tend to emphasize on activities that the external people can be involved in, in order to not exclude them. Therefore, it can be argued that then there is no longer a reason to join personally. People also psychologically behave different, especially more passively, if what they say and do is sent “to the world”.
We should focus on exploiting what is possible locally, and make use of the face-to-face opportunities. For bringing people together globally, we have the Fedora Social hour, or the respective meetings of the SIGs.
However, I like the idea to also make a “small conference”-like event at some point, which might indeed be complemented by hybrid formats. But I would first observe how things develop over some time, and identify what “shapes” Fedora London.