On the treason issue, the actual charge is
Aiding the enemy. I think it's a bit of a stretch. I can see the case for it and would understand him being found guilty, but at the same time think that the lesser charges are a more fitting description of his actions. Especially the computer espionage act;
(1) having knowingly accessed a computer without authorization or exceeding authorized access, and by means of such conduct having obtained information that has been determined by the United States Government pursuant to an Executive order or statute to require protection against unauthorized disclosure for reasons of national defense or foreign relations, or any restricted data, as defined in paragraph y. of section 11 of the Atomic Energy Act of 1954, with reason to believe that such information so obtained could be used to the injury of the United States, or to the advantage of any foreign nation willfully communicates, delivers, transmits, or causes to be communicated, delivered, or transmitted, or attempts to communicate, deliver, transmit or cause to be communicated, delivered, or transmitted the same to any person not entitled to receive it, or willfully retains the same and fails to deliver it to the officer or employee of the United States entitled to receive it;
Also note conspiracy theorists; that particular law falls under
RICO (and for that extra tinfoil crunch it was added to the RICO list by the Patriot Act).
As to his illegal detention and torture, his treatment was disgusting and he is owed compensation. I expect him to bring a suit against the government for that. I would note though that he will have a hard fight. A goodly portion of his detention was entirely valid given the stated legal circumstances. He is going to be reliant on medical reports to show that the POI status (and later suicide watch) he was put under was invalid, simply because a lot of what he was subjected to was justified under those rules. The legal powers gained over a subject ruled to be suicidal or otherwise a risk to themselves are pretty scary. It does sound like these statuses were abused to me, although I am largely basing that on statements from his legal team.
And just for the record I strongly disagree with the idea that any potential worse treatment justifies poor treatment of detainees and prisoners. I also disagree with the idea that Manning could have been treated worse legally or even punished more summarily. The American military justice system is more robust than that and rapidly moving towards the civilian system (amusingly, partially being dragged by military tribunals having to deal with terrorism cases more suited to civilian courts).