According to the official statement from November, significant progress have been made in the recent months and the campaign is closer to completion, though there is still some remaining work to be done and the team wants to prioritise quality over rushing with the release. They have an undisclosed release schedule, so you can be sure the campaign will be out at some point in future, just be patient.
I guess if you are generally fault-finding and overly critical as a person, then very few fan missions will be satisfying to your standards. I have enjoyed playing this mission even during the beta phase. There are a couple of things I liked less, but for me it's a solid 8/10, especially since this is the author's debut.
I can't believe I haven't played that mission before. I finished it today and Curse of the Ancients is indeed a forgotten gem. I agree with you about the underused spaces and for me this is the only flaw of this mission. Otherwise it's a spectacular achievement and we need to remember it was made in 2000. I really enjoyed solving the puzzles in the tombs, they were pretty much straightforward and I never felt stuck for longer than a few minutes. Exploring the haunted city was a sheer pleasure...
Looks like we've got completely different criteria for rating fan missions, because I think this is one of the best and most enjoyable city missions. It's not about blocky design or boring textures (I agree with this to some extent), but fantastic atmosphere, good storyline, and sheer vastness of the level.
It's a nice fun mission to play on one's lunch break, but that's all. I wish there was something more than "get down as fast as you can without dying" to this level. A few additional obstacles (such as archers) or hidden nooks and crannies with loot would make it more enjoyable and challenging.