There are canal tours - don't know if they can be booked in advance. And there are lots of museums and art galleries. Could there be some kind of walking tour? And there are horse and carriage rides - again, think you just negotiate with he blokes on the spot.
Not V helpful,sorry.
There are daily balloon flights over the city:
https://www.bruges-ballooning.com/en
(If your browser questions the security certificate on that site, don't worry; it's safe to visit it).
Yo might also like to check out what's available in Oostende (which is only ¼ hour away by train - it's a frequent service):
http://www.visitoostende.be/en