This is interestin' fer a few reasons.
Well, though it technically wouldn't infringe upon copyright as a "similar" game with an updated engine and different concepts of gameplay; it would have to have a drastically different name, different models, maps, etc., or it may be called out for plagiarism, even if we still have the same staff. If pulled off correctly, this would make many people happy, as it would be clean, easily updatable, and would possibly have better Mac and Linux access. However, just as many people may be unhappy with this, as they might not want to leave their beloved FeralHeart behind.
One may argue, "why not just have both," however, runnin' a server of any kind is EXTREMELY demandin', difficult and taxin' to the person's computer. Not only would it b 2 games to manage, but unless we could find a volunteer to run a massively multiplayer game server for free, which would require a very expensive computer, and would restrict access to the person's computer while the server is running; I doubt that would be so easy. We're so incredibly lucky to have Raz, which is hopefully well acknowledged, and unless we shut down the original Feralheart, it would be near impossible to run both.
There would also be the issue of forums. The game would require a new website and forum, which wouldn't be as hard as a new game, but it would be quite the regrettable move for many users, especially those with great dedication to their title and post count.
And then there's the issue of creating the game itself. Now I've taken a few classes in game design. I semi-successfully made a singleplayer, first person adventure game. It cost about $100 for the design program alone, took an entire summer, was incredibly buggy, and could not be run on any other computer, unless they downloaded the engine I use to make the game. Now, first person adventures are probably the easiest games to make from scratch. Third person, massively multiplayer games with high customization and add-ons would be so incredibly difficult to run smoothly. New models, new maps, coding from scratch to match the new engine, the recurring server issue, animations and so much more. Even the new updated FeralHeart took over 3 years to make, and that's just new maps and animations. Imagine how long it would take with Feralheart's current resources to make a new game from scratch.
tl;dr:
It's definitely not a bad idea to reverse engineer the game, though I'm not sure it would be possible with our current resources.
Still a nice idea though, Crusoe. Floofin' ye.