If that's how we're lookin' at it, Heroes is just a copy of WoW, which is a copy of whatever came before it, and so on.
This mod only shares a little in common with Heroes, and has a much wider scope. It's adding new gear/items, stats, mobs, dungeons, an entirely new combat system - even if it is similar to Heroes. Skills seem to be the only thing being derived from Heroes, and I really doubt this is where the ideas for those skills came from.