Well it looks like the archives are down, and have been for several days; if that's true, then it's really the end. Doom's great strength is that (nearly) every map ever made could be found in one place; if it all spread across different websites nobody'd be able to find your new wad when you finish it.
My CC3 map is a bit of a disaster. I've already missed two deadlines because a) the usual Yadex effect (god damn I hate that program) and b) whenever I playtest the thing I can't shake the feeling it's a convoluted mess of ugliness and contrived gameplay. However, I'm not starting again, not now. But whenever I look at it in yadex I go "ugh, can't face this" and close the window again.
Why you shouldn't write a review not having played the whole thing
Hellfire, despite a promising start, is turning out to be a disappointment. Let's see, I was in the middle of map 4. Well soon after I posted, I reached one of those mass start blinking effects which turned off all the lights in the towerblock. Combined with a lack of health (made more irritating by being locked out of the start area where I knew there were two untouched medikits - I loathe maps that permanently prevent backtracking) and lots of zombies, it made it all very very annoying. Pandora's Pox was a good example of how to use the start blinking effect - here, it was too pervasive.
Then I made several attempts to do map 5 from scratch, and failed all of them very quickly. You start apparently on an electric chair in a prison (recall Ksutra map 11) That's not a problem. Having no health and hardly any ammunition, however, is, and I got fed up of running out and dying. I gave up, returned to my savegame at the end of map 4 and began to carry ammunition forward. The prison interior wasn't too bad, albeit slightly repetitive and full of wolfenstein guards. Outside was bad, you have chaingunners everywhere, far off and at different heights, so you can't shoot them. There's a secret megasphere which hardly lasted any time at all. So frustrating.
Map 6 was equally irritating, being a maze of caves again with the characteristic lack of resources; map 7, back in a town, this time with freedom to roam, was much better. At least it would have been but there's mancubi everywhere and the usual lack of resources. There's no way I would bother with this stuff from scratch, you'd just die, weaponless and destitute. Having said that, if you have weapons and stuff, and you like exploring, map 7 is definitely recommendable. I enjoyed the creepy girl pinup too.
Then we get on to the Hell levels which begin at map 21. These are just as annoyingly limited, but since you've had to warp to get to them you don't have the luxury of reloading a savegame! (I suppose there's always playing the original maps 8-20 to amass resources but that is questionable to say the least) Although I beat map 21 after about 50 reloads I am stuck a way into map 22 with no ammunition and no health, and I pretty much give up, it's not worth wasting more time on this.