Exactly, Spfamy1.

I subscribe to every word you say, and I underline it 10 times.
GitHub
was/is the ideal option to report bugs and track feature requests. I find it really regrettable that Kris asked us not to use GitHub for now. I hope we will soon be able to use Marvin's GitHub again, for all the reasons you mention. These MobileRead forums are no replacement for GitHub. This is chaos. Half the time here, you just need to deflect trolls and personal attacks. No real clarity is possible here.
On the other hand, I understand Kris must be totally overwhelmed by all the feedback he's been getting in recent weeks. When I asked a friend of mine why he ditched Marvin a year ago or so, he replied something like: "Well, it's a one-man project – I admire this Marvin creator, but I don't think he can really handle this in the long run." And I fear there is some truth in what he says. Really, it's absolutely amazing that Kris on his own has been able to create e-reader software that is clearly superior over iBooks, Kindle, and all the rest of the competition – software that is inferior despite, in some cases, being developed by multi-billion corporations with thousands of staff members. Corporations just aren't interested in creating
top-quality software; they know that broad masses of users are perfectly fine with
mediocre software, and masses are where the big money is.

But there is reason to fear whether such a stupendous "one-man project" as Marvin really is sustainable for the long run. We must be careful not to overtax Kris with our demands. He overtaxed
himself in the Marvin 2 and Marvin 1 days, and then came the burnout that lasted for a couple of years; let's not repeat that experience.
Bad news is also that everything you say in your post likewise applies to the Beta-testing of Marvin 3. I have mentioned several times how disappointed I am with Marvin 3 Beta-testing – it was pretty much "kept a secret", with no interaction among Beta-testers whatsoever. This brings all the disadvantages you mention in your post. And, I fear, this – especially – brought about many deficiencies currently present in Marvin 3 that could have been avoided if Marvin 3 Beta-testing had been conducted in the same
interactive, collective way it used to be in Marvin 2 and Marvin 1 days. Marvin Beta-testing used to be about
teamwork; but now it's just a series of individual conversations with the developer, kept secret from the rest of the Beta-testing team.

The results in Marvin 3 speak for themselves; in its current state, I call Marvin 3, overall, a disappointment, although I do have hopes for the future.