If you decide on visiting FOSDEM, i too plan on being arround there next year.
Also, while in brussels, you should visit the Delirium Bar
They hold one of the worlds best selections of beer. Accros the street Is a place called Floris, that specialises in Abshint and one for whiskey but i dont remember the name.
So you are still in .eu? In this case (and in case of more general interest) I will give you an update on more events:
2018-04-21 Linux Presentation Day 2018.1 (many places)
2018-04-20 - 2018-06-24 Linuxwochen, Austria (many places)
2018-07-07 - 2018-07-12 RMLL, Strasbourg, France
(there are other more regional ones, but I try to stick to bigger events)
"OggCamp is an unconference celebrating Free Culture, Free and Open Source Software, hardware hacking, digital rights, and all manner of collaborative cultural activities and is committed to creating a conference that is as inclusive as possible. If you’ve got a story to tell, no matter your background or current status, whether it’s your first talk or you’ve loads of experience, as long as the talk is connected (somehow) to our theme then we want to know about it. "