[mc10]

Creating a CMS is a nice project to embark on, but there are a number of issues with maintaining a custom-made CMS. The first and most important issue (probably) is security: I personally don't think that hand-made CMSs will contain the security patches that more established CMSs (WordPress, Drupal, etc.) will have. Another issue is the (possible) high learning curve with making a CMS.

That said, if your team wants to make a CMS, go ahead! I'd personally recommend, however, using a CMS like WordPress for a production site.