It’s a good idea to get feedback on your theme, especially if you are tinkering with things like colors and font sizes. I’m only ambitious enough to modify blogger themes, but one time when I tweaked it, I didn’t find out until a few months later that the text and background colors I’d picked were hard on some people’s eyes. I thanked the poor soul who told me and quickly changed it.

It’s also worth pointing out that the over-all design and color scheme of your blog makes a big first impression. If I open a blog and see a hot pink background with purple letters and animated heart headers (we’ve all seen those stereotypical jr. high girl xanga and myspace pages), I’m probably not going to take what you write as seriously as someone who has a little bit more…mature look.