Changing the WordPress theme once you’ve invested valuable time and energy into building and customizing your author website is not advisable. I know because, as I’ve mentioned in previous posts, I learn things the hard way.
When I set up my original author website, I used the Twenty-Eleven WordPress default theme, only to discover later that there were themes available built especially for authors.
Unfortunately, there are hundreds of author themes to choose from, and, for the technologically disadvantaged like me, a lot of choice is not always a good thing. I threw up my arms and called it a day after viewing only a fraction of them.
Also, not all themes are created equal. Some, if uploaded from outside the official WordPress Theme Directory, are actually unsafe.
Add to that, the fact that website themes involve customizations that aren’t easily transferable if you decide to switch to another theme later.