[eluser]WanWizard[/eluser]
As always, it's about picking the right tool for the job, considering the person holding the tool...
CodeIgniter is simple, easy to learn, easy to understand, well documented, and reasonably well suited for beginners and the simple work. It's been around for dogs years, and hardly changed in that time, so there's a lot of info around.
CodeIgniter is crap if you want to make something big, complex, modular and extendable. And in terms of evolution it's stuck in PHP4 days, and dead (as any work to modernize it will not make it CodeIgniter anymore).
Having "tons" of external stuff just makes it worse, it increases the complexity, things don't work together, and before you know it you're extending half the core. Which makes the end result bloated, big, slow and impossible to maintain.
ymmv, see line 1...