One consideration that can affect many components in your home is the allergies of the people who live in it. The adjustments that can help depend on the item(s) causing the allergic reaction. Allergies can become more or less severe over time, moreover, anyone can can develop an allergy at any point of one's life.
Allergies to dust, or more specifically dust mites, can be alleviated by reducing the things that can hold dust and additional cleaning. For instance, wood floors are easier to keep dust free than carpeted floors. Curtains can also hold dust. Dust from higher up to lower and then vacuum.
Plant allergies are usually easier to handle within a home, and the near environment, if you have control over the yard or no yard. If the allergy is to an indoor plant, consider getting rid of it or moving it outdoors. If it's to an outdoor plant, can you get rid of that plant? Or if it's too common, like grass, could someone else mow the lawn? Some plant, like oak trees, have flowers in the spring. They may not cause an allergic reaction at other times.
Allergies to food can be extremely dangerous. Even when they are initially mild, they can get worse and be life threatening. If you need to have the food in the house, keep it away from other foods. Keep it clearly labeled. Make sure any babysitters know about it.
Pet allergies are complicated. If you test for allergies before adopting a pet, you can find out which ones will cause trouble for your household. But sometimes a pet ends up as part of the family through marriage or other blending. And as a beloved family member you may want to find a way to keep it. Or the residents may not be allergic, but guests may be. Depending on how long the guests will be staying and which rooms of the home they will be visiting, your strategy could vary. But some things that could help are surfaces that make it easier to clean up the hair and a good vacuum cleaner. There are also air filters that can help clear pet hair, dander and other allergens, like dust and pollen out of the air.
Perfumes are added to many common household and cosmetic items. Even magazines can have inserts with perfume samples. These can usually be eliminated more easily by buying a different brand or fragrance free versions of the household items. Throw out the magazine inserts; in more extreme cases, you may need to check magazines and things before bringing them into the house. (Perhaps using a clear plastic bag to hold the magazine while you examine it, could help.)