Yast is great central tool to tweak and configure servers and I just wish all distro's come with it. Webmin and the other range of web interfaces do the job of basic configurations but I would not want to do root work over the web on production servers. Yast happens to the only thing I liked about *SUSE that would make me switch from Ubuntu to it. Theme wise I do not see which one is worse, Ubuntu's brown or OpenSUSE green. I personally do not like either one of those colors for a Desktop.
CentOS brings the same features and benefits that RedHat offers at an affordable price $0. It offers the Linux community a secure/stable distro such as RedHat at a price one cannot afford to pass. Makes it a great distro for a data center or where one must run Linux and make sure the OS is patched decreasing cost adding value. The drawback is that you are running a kernel from a few months/years ago but contains some features that are backported from current kernel. On the other side, I have never been thrilled with RPMs and prefer the Debian package format.
Fact, FreeBSD and its port collection is wonderful. It is so good that my future servers are based on it. So easy to use, stable and with so many packages available makes it for the perfect server. Aside from the fact that is a very secure OS and have a extensive software collection it is easy to install and offers in my opinion the best file system available today, ZFS. I strongly feel that FreeBSD could one day become the best server OS while Linux the perfect Desktop OS but only time will tell. Development of FreeBSD is a bit slower compared to Linux perhaps due to the smaller community behind it.With that said, these are my opinions and I strongly believe there is no such thing as "The Perfect Distro/OS" as one release does certain things better than the other. In the end System Administrators are more concerned with system stability/uptime, data security, customer satisfaction and last easy to use and manage. It is hard and perhaps idiotic to put my 2 cents to a subject that has gone thorough a lot of heated discussions over the pass years and never reaches a conclusive winner. The winner is perhaps the people that are empowered by having the freedom to choose on what to use.