I'm still getting the hang of this form thing.
As far as the post, I think it depends on several factors. First, the kind of improvements. Studies have shown that updating kitchens and bathrooms add the most value to your home.
Simple, cheap fixes such as putting a fresh coat of paint on the front door, planting flowers, and replacing old hardware on cabinets, etc., is almost always worth it.
But you also have to pay attention to the value of the homes around yours. If you renovate your house so much that it becomes the nicest one in the neighborhood, you may put your home out of the price range of those who are looking to buy in your neighborhood.