The "Eloquent is not suitable for Large/Scalable project" is a weird meta

It's BS. :)

I'd say that, for 80% of the web apps you could possibly build, Eloquent/Active Record is perfectly fine.

Plenty of folks would laugh at me for saying that, but who cares.

I didn't read the whole discussion. But if you want to know how doctrine work, you'll can just read the documentation on Symfony 2.

Doctrine is just an other ORM, it's not complicate to use it on Laravel.