Have you ever managed several separate Drupal sites with 200+ modules? Not only that but there are so many people working on different things at different skill levels that just about all them are out of sync from the db snapshot to files that are suppose to be version controlled? I can tell you this… it is not fun. In addition, you have people who have no f**kin clue what they are doing installing modules and even asking for "slight" changes to these modules. Yeah… Drupal is pretty powerful but man can it be nightmare to manage if people who do not understand the ramifications of certain actions start doing things other than creating content.
Not to mention I can easily say that following code in Drupal is god damn night mare due to hooks. Very flexible but what a headache in regards to debugging code. Than you have to deal with all the little caveats like how caching works, what gets cached when and the different way module developers implement similar concepts in different manors. It really is a pain unless you are lucky enough to be able to push out sites and never see them again and lock down everything besides creating content for average users. On top of all this you have to put up with trash that Views, Panels, Fields, Webforms, ect churn out for HTML. In addition, people who developed Drupal and those that develop modules have no f**kin idea what error handling is. Everyone always just assumes things will work and when they don't it just about impossible to figure out why.
There are plenty of disadvantages of Drupal. I'm sure most custom frameworks out there are about 100 times easier to manage than a medium to large Drupal site that has it's share of modules and people of different skill levels working on different things. Powerful yes, but a nightmare to maintain. It works great until something breaks… that just about sums up Drupal. Though to build anything as powerful and flexible as Drupa w/ popular modules would probably take years. So it is a trade-off. One very little skill level can accomplish a lot without writing any code given the correct collection of modules. I have a love/hate relationship with it myself for all the reasons I mentioned. Even so I'm building my portfolio site with 7 as we speak. Though I can see already that there is going to be quit a it of work involved in cleaning up the HTML… but it is a trade-off. I do have a CMF of my own but I would be ignorant to say it is anywhere near as powerful or stable as Drupal w/ Views, Fields, WebForm, features, etc.
There is always the other option of using a Framework rather a CMS. Perhaps take a look at Symfony 2. In my opinion it is the best PHP framework that exists at this time. However, would I use it for my own little portfolio site – hell no. However, if I were developing a medium – large scale web application with a moderate budget I would absolutely use Symfony 2.
One thing you always have to understand is that many open source projects at this point have had years and years of work put into them. If you have ever used Drupal 5 or Symfony 1 you would see that man… do these things come a long way. Depending on what the requirements of a project is it *probably isn't worth reinventing the wheel. Besides unless you have a 50K+ budget to play with it normally is pretty impractical to start from the gruond up without at least using a framework. Even when you talk about a Framework that is probably around a 20K+ budget starting considering everything still have to be prgrammed and designs from an admin to front-end. Most people tend to stick between 5K – 10K which is generally cause for some type of CMS considering *most of the hard code programming is complete and an admin system exists. Than you have your under 5K budget which is generally WP…