Many Tolkien scholars will buy Arda Reconstructed to use as a valuable reference on the sources of each paragraph in the published Silmarillion, and also to ponder and then respond to the analysis and provocative conclusions of the author. Then there will be other more casual Tolkien readers, like me, who may just be curious.
I came here to thank Voronwë for writing AR, and to explain why it's an important book to me (and probably to others like me). I am certainly not a Tolkien scholar, but I AM an avid student of Tolkien, and have been for over 35 years.
First, a bit of background: I fell under the spell of Tolkien in middle school, and I read both TH and LOTR repeatedly during my high school years in the 70s. I was especially fascinated by the references to the underlying mythology and the info in the appendices which gave enticing glimpses into the legendarium.
I was in college when the Silmarillion was released, and I bought a first edition copy when it arrived in the bookstore (I still have it!). I was completely mesmerized by the book, and kept it on my bedside table through the rest of college and grad school. It proved a wonderful distraction from the stress of academic life. I read some of it each evening. It was such a great way to wind down! Years later Tolkien's works still fascinate and entrance me. I do love to read, and so naturally I've read many other books, but I always come back to Tolkien's books. Over the years I acquired UT, CoH, as well as Foster and Fonstad as references. I even became enough of a "Tolk-head" to write a 30 page primer on Middle-earth for a Tolkien book group which I led for a while. The Silmarillion has always been the center of it all for me. It still is.
Fast forward to Spring 2009: I had not yet crossed the boundary into the "perilous realm" of the HoMe, or any of the many other volumes written by Tolkien experts, but I had a good handle on the legendarium, and I simply enjoyed reading and delving in to what I already had. Then along came AR, which I read about online, and it threw a wrench (or more accurately a whole toolbox) into the works. How? Well, the author supposedly stated that the Silmarillion omitted a lot of important material, and concluded that it could have been better! What? My beloved Silmarillion? Better? Well, I just had to take a look!
I started reading AR about 7 PM the day it got here from Amazon. By midnight I was online ordering the 3 vol. complete HoMe, because I just HAD to read the omitted parts, plus the alternate versions in the various manuscripts (QS, LQ. AAm, GA etc.). I was hooked!! Within days of receiving the HoMe I was back online ordering some of the Hammond and Scull books, then Carpenter's bio, then Shippey's RtMe, then Letters, and now I fear (as does my wife) that this is only the beginning! So V., I'm not sure whether to thank you or to curse you!

In all seriousness, I do want to sincerely thank you Voronwë for your incredible detailed work of scholarship. The organization, layout, tables and concise, clean writing style of Arda Reconstructed makes it pleasurable to read and efficient to use as a bridge between the Silmarillion and the Silm-related parts of the HoMe. For me in particular, AR has served as a catalyst. It has inspired me to look deeper and deeper into the sources of the Silmarillion and the legendarium in general, and it has led me to read for the first time many important and beautiful passages and stories that were not included in the published version. It's been like discovering a new room in my house that I never knew was there (which is a good thing because I'm going to need a new room to hold all these books!).
I also thank you for including your provocative opinions and conclusions which have led to so much interesting conversation and lively debate, here and elsewhere. I don't feel qualified at this point to weigh-in on all of your individual conclusions. I will say, however, after reading the published Silmarillion again, with AR on one side and the HoMe on the other, that I do agree with you whole-heartedly that the text could have been substantially enriched, and the development of many characters greatly enhanced if the published version had included the omitted passages, stories and sections you discuss.
I suppose there's no point in wishing for the literary equivalent of an "expanded director's cut" edition of the Silmarillion (sigh!) Of course the good news is, thanks to Christopher Tolkien's other monumental works (HoMe, UT, CoH), nothing is completely lost. It's all (or mostly all) there. We just have to be willing to hop back and forth between books a bit. And now with AR to expertly and explicitly guide us as we hop, we can all more easily enjoy reading the Silmarillion at an expanded and richer level. That is the version of the Silmarillion I will choose to read from now on. So will this Tolkien student become a Tolkien scholar? Doubtful. But I do feel like my quest to understand Tolkien's world has entered a new phase of deeper investigation, and that is exciting enough for now!
Ok, time to stop. This has been a long post. If anybody is still awake, let me say thanks for "listening"! I initially came here just to thank V. for AR, but when I looked around I felt like this was an interesting as well as a comfy place to pull up a chair, so I decided to join, if only to bask in the presence of those who know so much about the books that I love so much. I look forward to getting to know you!