Night city is actually pretty damn good so far

[Yup]

Nobody can own him yet, neither does he.

But that's not what Rags' signature would allude to

[Yup]

Is there a 10th SQ that appears if you get all the skulls in madness?

Not here.

All skulls collected, just one new skull quest....Gold and Souls Vault (Not a horde or cache.. but a vault! )

[GotN]

But that's not what Rags' signature would allude to

You can't miss something what you can't get