Plants release oxygen, which is good

My new project when I get home is Plant Maintenance. I've got house plants that need to be re-potted, re-soiled, and upgraded into bigger pots, as well. In a nifty bit of trickery, my cactus also needs to be re-potted. (How does one re-pot a cactus? Very carefully. I've got gloves, and I am afraid, so I'll use them.) But I've got several plants that need some tender, loving care. Something interesting I came across on the Internets today is an article, "11 Signs of an Unhappy Houseplant." This article landing in my lap in so timely a manner is reason to pay attention. Herewith, some of my plant issues, copied and pasted from the article:
Symptom: Spindly Plants, Few Flowers
Possible Cause: Poor lighting conditions.
Management: Most indoor plants need an average of 14 hours of sunlight each day. Do an Internet search to find out the proper amount of direct light, indirect light, or shade that your particular plant requires to thrive.
Symptom: Yellowing Leaves
Possible Causes: Overwatering, low humidity, poor soil drainage, low temperatures, or pot-bound roots.
Management: If the weather has changed suddenly, make sure that your plant is not in a draft, near a heater, or reacting to an unexpected environmental change. Check that your pot has adequate drainage and that the plant isn't root bound.
Symptom: Brown Leaf Tips
Possible Causes: Too much fertilizer or pesticides, dry soil, low temperature, hot air, accumulated salts, or root rot.
Management: It bears repeating—most indoor plants need to be fertilized only once a month, at most. Stand pots in shallow, pebble-lined trays that are filled with water to increase humidity (pots should sit on the pebbles, above the water line). Once a month, apply enough water to the top of the soil to thoroughly flush excess salts through the drainage hole.
Symptom: Small Leaves or Wilting Plant
Possible Causes: Soil remains either too wet or too dry.
Management: Develop a watering routine that is infrequent but deep to promote healthy root growth and combat root rot. If root rot is suspected, remove the plant from its container, examine the root system, and cut out infected roots (blackened root tips with slimy decay), then re-pot using sterile potting mix and a clean pot.
Something that didn't occur to me until I was reading this, is that I can re-pot and re-soil a plant in the same pot it's already in, just with fresh soil. I'll tell you right now though, I'm not going to be putting my pots in plates full of pebbles and water. But I do notice that a few of these are exactly what some of my issues are. I get brown leaf tips on one of my spaths, and I get yellowing leaves on my dieffenbachia. I need to be better about checking the soil's wetness before I water, and I think the re-potting will be a huge help to them all. This will not be a quick project. And I'll need more than the one bag of potting soil Mom bought for me today. I need a new pot or two, and also a couple new plants for some empty spaces in the house.