Quality is definitely better than quantity. In doing your keyword research you have to take note of including your keywords or phrases in the content, h2 - h4 headers, description and title. So easier to optimise for a few really good keywords, than trying to cast your net too wide. We generally do three for the home page, and two per internal page.
How about if you only target one keyword per page but you end up using other key words in description etc, is that still counted as keyword stuffing?
When including keywords in content try and write in a human readable way, if humans are going to read something they may get put off if something reads oddly to them, if you write naturally you will find yourself placing the keywords anyway.