I'd say the first RL to make ranged combat (as the main playstyle) not annoying is pretty original.
What original it is when it's copied from Doom? Don't let ascii fool you. DoomRL is an ascii version of Doom. It's not even a roguelike.
Of course DoomRL is an ascii version of Doom. They're not making *any* effort to claim otherwise. If anything it's like the Slashie.net RLs; a straight up tribute/what if game X was a RL.
Also, how is it not a roguelike. I'm pretty douchey when it comes to letting games call themselves a roguelike, and even I don't see anything wrong with DoomRL's claim?
Combat is unimodal, it's turn-based, tile-based, has resource management, levels are procedurally generated, death is permanent. I'm pretty sure you can even go back to ascii mode if you so wish.
Aside from the first level being static and there not being an identification system in place I don't see what's NOT RL about it, but feel free to point it out, you've made me quite curious.