When looking at CMS design you need to consider the people that will have access to the CMS system itself. In most cases it isn't necessary to brand the design, however a visually appealing design will make the CMS system more intuitive to use. Most content management systems offer a graphic user interface or admin panel. These are similar to most editing programs and word processors so the majority of people can simply pick them up and start using them immediately.
CMS hosting is another factor to take into consideration. Depending on the CMS system you use it may be necessary to find CMS hosting that offers support for ASP, PHP, JSP or another scripting language. While it is important to look around for CMS hosting that offers this support you should also consider access and look for hosts that offer the appropriate databases.