One of the challenges with Final Cut Pro’s “Simple Border” effect is that it will not work if you crop the image. There are work arounds for this but I found a better solution. BretFX’s Better Border is a free plugin for Final Cut that allows you to crop and put on a border with one tool. I had a pretty complex border project (personal) and wouldn’t have been able to do it without this tool.
Check out the site as there are other reasonably priced plugins such as their Splitz effect that might make compositing multiple speakers much quicker.