Thanks for catching the paragon issue. I play with the max fury, and I just forgot to mention it in the guide. There's another setup that drops the Illusory boots and runs with IK instead of Raekor, but that's not the focus of this guide. Any immunity neck will do, take the one you like. I haven't personally seen the lag from the Overwhelming desire, but if that is an issue than I would just stick with an immunity neck or a Hellfire. As far as the War Cry rune, again my personal preference for the GR's that my group is running is to use Veteran's warning, but that's me. Also thanks if you were the user that upvoted the guide!
I got tired of looking for HC builds without much success. I've thrown together a build for each spot in a standard four man party with a focus on HC. There are links/previews for all four builds inside each build for easy navigation. Below is the link/preview to the Barb build. Let me know what you guys think.