Forum Moderators: phranque
You basically need something that's really comfortable for you to use, and if you come from a Frontpage background, you'll probably want the advanced properties and technical parts of it hidden from your view - but always make sure this is available if you want to find it. The worst thing ever is having to go back to a programmer and pay him more money to fix things up again. Well, not the worst thing for me, since I'm usually the programmer :)
It will also depend heavily on what kind of content you're managing. I tell my clients to just imagine how they'd like to go about their daily content management. Then I build around their specs (or, usually, end up offering better solutions). The programmer(s) you're working with, if they built a CMS before, should be of great help with suggestions and design practices.