The location is excellent. The space is very minimally appointed, as in: What is necessary and sufficient, almost. I have made suggestions to the host about marginal improvements that would make magnitudes of impact...
Things that will be hard to address, however, include the commotion of the downstairs kitchen (the room is above the restaurant), loud voices and stomping up and down in the stairwell at all hours, and the noise of the upstairs neighbors... So, if you decide to stay here, bring earplugs.
Unfortunately, you cannot bring nose-plugs, and kitchen smells permeate the room all hours of the day, starting very early. I'm a big fan of breakfast, but being woke to the smell of frying food every morning is a bit heavy.
On the plus side, this is an imperfect little place that is all your own. The hosts from the restaurant are super thoughtful and kind. Just a little more effort and this tiny pied-a-terre in Brussels could be a dream. :)