The Queen is a renowned gardener and takes an interest in photography. L'Evallier and wife, Melanbury, take a huge interest in the fine arts, especially portraiture. Rodish, and later Balkish, like hill walking and will sometimes spend some time with relatives going back to their old traditional jobs of mining. Roherum reads a lot and from across the universes to try to improve his knowledge though the weatherman insists it isn't working as the goblin is still as thick as two short planks. The weatherman got an "accidental on purpose" thump on the back which made him slide across FNN's main studio floor for that insult.
Eileen also likes gardening. Hanastrew is a devotee of chocolate and loves reading up about it when she's not busily eating it. Brankaresh is far too interested in advancing his career by fair means or foul to take any time off to develop any hobbies at all. The Lord Chamberlain likes reading histories, usually of stately homes on planets like Earth, as he picks up ideas for improving standards in the Queen's Palace from these.
Hobbies can also give characters an excuse to meet, something to talk about when other topics are awkward, can endanger them or save them. All in all they should add depth to your characters and as a result to your story too.