I've had my Chromebook for about a year and a half now, and it's been nothing but great. It did take some getting used to, since Chrome OS is so different than Windows and Linux, but it really wasn't that bad. The main appeal is the simplicity. There's no clutter on the desktop, and everything does just enough to work, but doesn't get bloated with a myriad of little used features.
It might sound odd, but I enjoy the lack of configureability of my Chromebook. Either on Windows or any of the flavors of Linux desktop environments, constant tweaking usually ended up breaking something. Particularly in Linux, I've spent too many hours fighting with some widget's bug or the like trying to get it just the way I want it. It's a non-issue with Chromebooks, they just work right out of the box.
As for applications, I do spend most of my time either in the Chrome browser or on a Linux commandline; which is perfect for the Chromebook. It's quite easy to set up Crouton, which gets a full Linux environment. It runs while Chrome OS is still running too, so it's not a dual boot setup, but I actually prefer this. Many of the Linux desktop environments are nice, but none match the simplicity of Chrome OS. There are a wide range of shortcuts and hotkeys as well, which I find very appealing.
In my experience, Crouton runs best in headless mode. This works perfectly for me too, since I much prefer the commandline to graphical interfaces while I'm coding or working on a project. tmux + vim allows me to do everything I need quickly and efficiently. The Secure Shell app for Chrome works wonderfully with Crouton, once you set it up to run an SSH server on localhost. It intercepts all the usual commandline hotkeys instead of Chrome, which allows things like ctrl+w without closing your session.
When I need a full desktop environment, Chrome Remote Desktop (CRD) is an excellent option. I have an always-on Windows 10 installation with a CRD server running. Latency is handled very well, with excellent adaptation to different network conditions and quality. Though honestly, there are very few times where I find myself needing a "full" operating system. The Google Docs suite handles what little word processing and powerpoint work I do, and there are whole host of online applications for other sorts of tasks like image editing, music, and even programming language IDEs.
Image from us.toshiba.com