Disclaimer: I'm a dog person. I connect with dogs I always owned dogs. I'm not as familiar with felines but I do like them. I felt SF literature was biased somewhat in their favor and hence my post. I try to look at things from another angle. However I also try to mine existing ideas for new slants and I am a big fan of Andre Norton so: Cats in Space...
The Scouts have their dogs. Free Traders have their cats. The features that make cats less attractive to Scouts make them more attractive to traders. There is a difference between running a 200 ton commercial ship and a 100 ton explorer ship.
Free traders do not have the time or need to perform the strenuous decontamination procedures a Scout ship does almost weekly. They also do not explore untamed worlds but stick to the known markets for the most parts. Having vermin onboard is more of a factor and liable to put off high passage buyers. Cats excel in killing vermin and can be taught to present kills to the crew for rewards instead of eating them and poisoning themselves.
A popular trick on some merchant vessels is to shut down gravity to various areas to save maintenance on the grav plates. Many of these ships lay strips of carpet or velcro like materials allowing the cat to keep its footing using claws while mice and other stowaways try to swim in the air.
Commercial vessels also possess a steward who can devote more time to the care and training of a feline than a Scout medic busy treating bullet holes, stabbings and other symptoms of pirate attacks. The ship's cat usually has a locator chip (embedded or on its collar) to make finding it (relatively) easy.
Many cats are taught to seek their carrier at the sound of an alarm. The alarm sounds like an antique device called a can opener to some or a microwave oven to others. Of course many felines are defiant in the face of laser barrages and decompression (they have humans to take care of that stuff.) In the event of accident or attack he is the person responsible for seeing that a stubborn ship's cat is secured in its carrier or a safety ball. He also carries a tranquilizer hypo to make sure the cat stays in the safety ball for a few hours.
Sharp merchants will procure and nurture a cat that will attract high passengers (maybe several on a big ship like a liner or Type R). A flawlessly groomed feline can add to a ship's decor. Many pirates prize white Persians for some reason. This leads to another advantage of ship's cats that Scout dogs do not share: breeding them for fun and profit. While no Scout will ever entertain any insult to their dog the animals are of mixed breed. A well bred cat has turned credits for its owner by breeding services or the sale of their kittens. Many a deal was conducted with a kitten or two added to sweeten the terms.
Cat Skills and Tricks (as for dogs roll up 2-3 tricks.) All cats receive Hunter-1.
1) Can use a fresher (no litter box!)
2) Can operate a food dispenser
4) Steward (pluses to reactions from passengers.)
6) Survival (the cat can live off the land or ship for that matter for days or weeks without human care.)