Making a listing on one major exchnage is enough for altcoin growth. Another way is by creating working products and more utility for the project. Also having a great community who are enthusiastic about the project does help.
Exchange is not so important to the price increase of projects. The most important thing is that they need a large community to support them and have products to prove they are good projects. And from there they will get the attention of big organizations and the price can be pumped