I do not think that such a centralization is desirable. The Tor project has lost a lot of credibility for me after the treatment of one of its developers with flimsy accusations that happened to be the exact same accusations as leveled against Assange (also never proven) almost at the same time. Both Assange and that developer were outspoken critics of the NSA.

In other words, I consider the possibility that the Tor project is subverted, so why should I trust Tails now?