Great concept - it would be awesome as something like an Ubuntu remix.
But I'm a bit concerned with making Tor available by default to ordinary users. While Linux's average user has historically been a cut above the rest, Tor is *not* something you should have running if you don't understand exactly what it does.
The scenario I'm imagining is:
1 New user installs Tor-enabled Linux distro;
2 Tor runs in background;
3 User's computer gets used as an exit node by someone downloading child porn;
4 User gets arrested by local cops;
5a User, not knowing what Tor is, is unable to mount a strong defence; or
5b User, knowing what Tor is, complains bitterly at Linux distro for screwing them over.
A safer alternative might be to use one of the darknet protocols (I2P, Phantom), or to limit Tor usage to *.onion by default.