Something you can do in 5 minutes that will make the site a lot better: left-align your body text, increase line-height.
Center alignment works for titles and headers, sometimes. You never want to have blocks of text center-aligned, though, because it’s harder to read (lines don’t start in the same place, so you have to track for their beginnings).
Increasing the amount of white space between lines of text also increases readability.
