In selecting a cat to adopt your main or sole criteria might be easy maintenance! 😎 A fair point. The question is ‘which cat?’ I guess this means either an individual cat or a type of cat or a breed of cat. The answer is clear to me. The cat which is easiest to maintain is a female, random-bred cat (moggie) with a cautious and gentle character and short non-white hair which has reached adulthood but not old age and which has a clean bill of health

Female – male
I don’t think you’ll see much science or any science on the topic of whether male or female cats are easier to take care of. It depends on how you care for them to a certain extent. The domestic cat most likely to get run over on the roads is the young male who is allowed to live an indoor/outdoor life. I’d say that males in general are more adventurous which predisposes them to exploring more and travelling further outside. This exposes them to being hit by a car which would result in a massive maintenance issue if they are badly injured.
I tend to favour a female over male in terms of ease of maintenance. I am generalising of course. There’ll be variation among individuals. Caution and slight timidity in domestic cats should mean that they live safer lives which translates to lower maintenance potentially.
Random-bred
I’ve chosen a moggie over a pedigree because purebred, pedigree cats are invariably inbred. They commonly suffer from inherited health issues. The best known is HM in the Bengal and Maine Coon (MC). The MC also suffers from spinal atrophy, hip dysplasia and patella luxation. All require more maintenance and possible insurance.
Some say the Sphynx purebred cat is an easy maintenance cat but they are wrong when compared to my choice. Relatively speaking there is a lot to do: regular wipe-downs, keep them inside, clean their ears to name three maintenance activities.
Cautious and slightly timid
The counterpoint is boisterous. Boisterous translates to potentially getting into tricky or hazardous situations which can negatively affect health leading to more maintenance. I prefer the female character. I stress that I am generalising. Some females will be more boisterous than some males.
Shorthaired
This one’s obvious. The close-lying short coat is self-maintaining. There is little need for human intervention but in contrast the cats with the longest fur, the Persian, need constant and regular grooming by their owner to prevent matting. Do you remember that photo of a rescued Persian who’d been badly neglected for years? The coat was horrendous. It was as if she was lugging around an alien creature on her back.

All longhaired, purebred cats need regular grooming by their owner. Shorthaired cats will benefit from a flea comb regularly which serves three purposes: bonding exercise, check for fleas and kill them when they are combed out and to comb the fur but shorthaired coats don’t normally need human grooming as the cat does all they need themselves.
Non-white coat
Non-white coats are healthier than all-white coats for this reason: they provide a degree of protection to the ear flaps from UVB light when the cat is allowed outside. White fur has no pigment in the hair strands. UVB goes through to the skin of ear flaps as fur is very thin there. This can cause skin damaged and cancer of the skin or solar dermatitis. My assessment under this heading is valid for cats that are allowed outside or allowed to sit in the sun in any environment which would include a catio which is exposed to the elements.

It goes without saying but I’ll say it: cancer of the ear flaps needs amputation of the ear flaps. An important surgical intervention at a cost. More maintenance.
Young versus old
Young cats are more likely to get into trouble. Old cats often like to sit and watch. No trouble. Less worry. Less chance of problems. Less maintenance potentially.
Clean bill of health
It is obvious but the adopted cat should be clear of health issues including genetically inherited health problems. The start of the adoption should be perfect in terms of health. This does not rule out three-legged cats and other cats with so-called disabilities. These are normally not health issues. They can make the cat safer than a fully-abled cat because they are less mobile. That said blind cats need a change in lifestyle by their owner but it is very manageable.
Tell me what you think. Disagree? I’d love to hear your reasons why.
Below are some pages on grooming.