Never mess your blog with too much of Adsense ads. It gives a confusing look to the blog.
Forums are good way to drive traffic if you are regularly posting something.
Add your personality - If you are writing on a particular topic, there are a number of people who will be writing on the same topic. So you need to add that specialty to your blog to make it look different and to allow your readers to take away something that the others are not offering.