If you have ever worked with the double values when you need precision, you might have came across a weird issue where you lost the precision of your value with a very little number. Like, when you add 0.1 3 times you get 0.30000000000000004 instead of 0.3.
OpenShift is great to run your small website or application in the cloud. The main advantage is, it gives free 3 small gears. It can easily handle your personal or small amount of traffic. But it gets into idle mode when not used for 24 hours. So if there isn't any HTTP request in 24 hours, your application will be in idle mode. And next time, when it receives the request it will take a little bit longer to respond as it needs to start your gear and then responds to the request.
WordPress was my first choice when I decided to start a blog. It provides so many features to customize the look and feel of your site. But going forward, I decided to move on from WordPress to Ghost - Just a blogging platform.
WordPress with OpenShift is a good choice. CloudFlare makes your site faster by serving your static contents and makes your site more secure. CloudFlare also provides a flexible SSL certificate for your site which adds more trust to the visitors. However, you might get into some trouble when you enable SSL.