- It's limited to 100 blog members / readers, and the member list is maintained using the Permissions wizard.
- It provides no activity log, showing maintenance or updates. This may present a challenge, in a team blog with multiple administrators.
- It provides no archiving of multiple historical versions of a given post.
- It provides no backup and restore capabilities, beyond the known manual processes.
- It provides no ability to transfer ownership of multiple blogs between one account and another, besides one blog at a time.
- It has no ability to allow multiple authors to work, simultaneously, on one post without the possibility of the work done by one overlaying another.
- It provides no index or statistics of posts by author.
- It has no capabilities for moving a post (and attached comments) from one blog member to another.
- It has no granularity to restrict access to specific posts in a blog.
- It provides no built in demographic analysis of blog readers.
- It provides no forms entry, natively, though you can add a data collection form, using a third party web site, if you wish.
- It includes a spell checker in the post editor, but it's light weight and not very configurable. The spell checker in Firefox and other browsers is more robust.
It's possible that you can suggest some of the above improvements, if Blogger is currently accepting suggestions. But don't design your blog based upon the hope that any of these will be provided soon, unless you enjoy being disappointed.
If you want a content management system, you purchase a content management system. Blogger is a good place to start, to develop a web site, but if you need additional capabilities, such as the examples provided above, it may be time for you to move on.