come to think of it, dedicated style classes for individual TYPES of links might be extremely useful - like for example, if the profile page links in posts (clickable usernames) had a dedicated style class, you'd be able to write a stylesheet with a little user icon if you wanted that.
you can easily keep the default style sheet simple and without repetitions still, while adding a lot more versatility and options for those who design styles.
also, one question - what's with the nested tables? looks like you've got two nested tables, both with disabled borders, where the outer table "emulates" a border by using a background color ... why not simply one table, use border-collapse, and use the border properties? you should get the exact same result...?