I really liked the old theme I was using (MistyLook), but I was having some trouble with it working properly. The sidebar which should appear to the right side was not behaving reliably, and would often only show at the bottom of the home page. This was probably a result of the wide text in some of the blog posts, which should have wrapped properly and handled this, but seem not to have done.
Another drawback with MistyLook is that it’s a fixed theme and doesn’t resize according to different browsers and window sizes. Which may be related to the above problem.
So I have now changed to a different WordPress theme, TwentyEleven. It’s not as atmospheric, but it seems to be working much better, and will resize to different window sizes. It should work better long-term.