Starting your website with Jekyll is the best of both words; you can find great templates that start you out with a professional looking website, and it is easy and fast to customize.
You can find tons of free themes and paid themes to start you off with a great looking website. Since there is a large community of Jekyll sites hosted for free via GitHub Pages, you can easily find a great open-source starter template, fork it on GitHub and start customizing. I forked the theme for this site from this template, modified it heavily and then created my own starter template with the changes I made. In keeping with GitHub style, the original author was able to pull some of my improvements back into his own template.
Free Hosting with GitHub Pages
While hosting on AWS or another cloud service can be had for extremely cheap these days, under $5 per month, it still costs money and requires you to set up the server and keep it running. Why pay for hosting when you can get it for free with GitHub Pages?! While the service has a few limitations on what you can do with Jekyll (no custom plugins), it overall works fantastic, especially considering the (lack of) cost.
Page History Archived with GIT
Of course you use some version of source control for all your projects, but it’s easy for a blog site to get looked over. With a WordPress site, you end up will all your precious posts in some hosted database doesn’t keep a completely history of edits and changes. You need to deal with database backups, custom plugins, and everything else needed to re-assemble your site if you ever need to migrate or shift it. With Jekyll, all you have is a single flat file structure that can be easily tracked with GIT.