When we looked at various portal and CMS solutions to replacing our aging legacy intranet portal, our committee evaluated about 10 different technology solutions and arrived at Adobe AEM as the best solution for us. It's not cheap, but while many competing solutions "CAN" meet requirements, it's worth the time to request a demo of "HOW" an editor and end user would use the platform and witness the steps involved to better understand the process.
One of the features I like the best about the product from layout and design perspective is that you can drag and drop column control components on a row by row basis to layout your page. Gone are the dark days when you are constricted to a 2 or 3 column layout template for the whole page. You can decide that you want 3 columns of content components (text, video, images, or widgets, etc.) in the first row, and then decide on the fly that you want 1 or 2 columns on the next row. This allows designers and authorers the flexibility to layout each page as needed without resorting to templates. Of course there are page templates as well, but this was one of the many selling points.
The fact that you can simply select text and in a couple clicks update the content makes updates easy, and encourages a culture of self publishing made easy.
The product definitely needs a 3rd party implimentor to set up the necessary templates, configurations, customizations of components and of course testing etc. Expect this to take at least a full year before actual launching the product - more if you want to ensure a truly bilingual experience for administrators and content editors.
I'd recommend getting some in-house expertise so you can determine which customizations and configurations can be done in-house (more cost-effective) and what can be implemented by a 3rd party provider.
We were looking to replace an aging oracle based portal intranet solution. We honestly aren't leveraging many of the marketing features and personalized content features yet, as we are focused mainly on migration from our old platform at this point.