Yes Mint and Cinnamon are customizable. Very in fact. You just need to locate the file that pertains to the aspect you want to change. There are ways to modify the file directly or you can also create your own extension to "monkey patch" the extension or aspect of choice. For you this would be the top menu. Rearranging the applets im sure can be done by this as well. Please read on.
Out of everything I have been researching this past week there is a blog that has some of the best articles on the net on the subject.
Ok sorry if you did not need any of that. But if it helps, great. Now to the point. the blog is: http://blog.fpmurphy.com
(This is a good starting point)
In the archives list on the left, in February there is a couple posts about Cinnamon.
This is another great post that teaches the reader how to add things by making there own scripts:
I hope this helps.