The biggest advantage from my point of view is that CI is very light and very fast.
It has minimal opinions so you can do things how you want.
Most of my work is small Web Applications and CI does this perfectly.
Laravel is a too heavy for a lot of these tasks.
A con of CI is there is a lot of hate for it in the PHP community - but so what - I use what works and what I'm familiar with.
Finally, if CI fell over tomorrow - the applications would still be easy to understand and could be maintained by anyone half competent.
