Why don't I have a custom title by now?!
1) Its very likely to be shut down by ID because it 'IS' a remake not requiring any of the original assets or even 'owning' a copy of the original game. This 'IS' illegal :(
I linked to projects that are remakes and yet, they don't appear to have come under fire -until now. Probably it's a case of "none cares".
Oh and, meet the granddaddy of all Doom remakes (N.B., this was made BEFORE the actual source code release and thus before actual unofficial source ports existed, in 1996 ;-)
At which point does something become "annoying" for id? Let's see...slapping the name "Doom" on your product (with a qualifier) seems to be A-OK. There are so many variants that I lost count: Doom 3D, Doom 2011, Doom for Java, Doom.NET, Doom 2D, etc. you name it.
Let's see...lookalike resources? I can see why this would be a problem (and Freedoom doesn't accept "too close" lookalikes), but many of those "remakes" actually use ripped resources, and in rare cases, reworked ones (the ZX one seem heavily reworked, but still clearly identifiable in most cases), and all is fine and dandy.
In the end, I think it's simply the sheer volume of the task at hands that makes overly ambitious projects collapse under their own weight, as it unfolds. A model and a texture don't make a game, unfortunately. Maybe a good first project for an apprentice/hobbyist game developer, but no more.
The above being said, I think Sahkan has some obvious talent in 3D modeling, and I'd rather see him contribute to a well-established project like Doom Ascension, which can never have too many modelers, than doom (pardon the pun) his work to obscurity or, worse, legal persecution (however unprobable).