I have a wordpress site that seems alright, hundreds of visitor coming in daily and I once a while updating the content. I am using a free theme and it so far OK however since I moved to a premium theme, besides it looks better, the traffic also increase significantly.
See what Jeremy Schoemaker has increased his website traffic after using this premium theme in his blog www.shoemoney.com
Why using a premium theme can increase the visitor traffic?Load faster, when your website loads faster than your competitor visitor will love it and stay longer with the website.
Responsive theme, means your website will show correctly in a mobile device and has good speed too, remember now people mostly visit from mobile devices.
What this means for your business... great user experience. People will love your website when it loads faster, they will happier when the appearance is simple and professional with the font that easy to read, not too small or too big.
When user loves a website they will start reading another post of the blog. It means bounce rate will become low. Bounce rate is a percentage of people leaving your website, the lower the better, means they stay long enough.
Google will now that your site is good therefor will put your website higher than other websites that's why your visitor increase as your position in the search result is in the top position.