Regarding Assange, there is some serious misinformation being passed around.
1) The allegations are certainly crimes under English law and explicitly include one count of rape. Both a magistrate's court and the English High Court reviewed this point and came to the same conclusions.
There is a summary here and the High Court's ruling can be found
here. Add to this the descriptions offered by
Assange's own lawyers and it looks like a very clear case of rape to me.
2) The British government did not threaten to storm the embassy nor has it done so. Rather they have maintained that they will arrest Assange once he leaves it and that they do not accept diplomatic asylum as a valid concept (consistent with European and British law; Ecuador is subject to
a convention of the Organisation of American States that recognises it but I do not believe anywhere outside that convention does).
Under UK and EU law, and the current state of the case against Assange, Britain has a clear mandate to extradite Assange to Sweden, with no clear human rights case to be made against this. The UK must seek to arrest and extradite him to their full ability. This means arresting him if he leaves the embassy, using diplomatic means to have him handed over by the embassy staff, or legal means to remove the embassy as an obstacle. This third path is the most controversial possible,
but is possible, either by temporarily breaking diplomatic ties (expelling their ambassador) or under the Diplomatic and Consular Premises Act 1987, which allowed for the revocation of diplomatic status where compatible with international law. This latter law was what the UK reminded Ecuador of in the letter they sent that was then taken as a threat of 'storming the embassy' by Ecuador's ambassador.
3) Assange's human rights are not at risk at any point. Very simply the UK and Sweden are both subject to the ECHR. This forbids extradition where someone may be subject to capital punishment, torture or inhumane treatment. Even if somehow he were to be extradited to the US, whichever nation he was in (or both if he were extradited from the UK to Sweden and still in their legal system, technically still partially under British care) would have to obtained guarantees that he would not be subject to such treatment before the extradition could proceed. The only path to anything approaching torture or the death penalty would come through extra-judicial and illegal means. I don't see how being in the care of the British or Swedish justice system is going to reduce such a threat.
On the other hand, I am not sure whether Ecuador have similar legal protections. They have a slightly spotty human rights record themselves, although to be fair (and slightly ironically) most of their recent significant rights violations have been with regard to
freedom of speech. I haven't seen anything to suggest they would have to refuse an extradition to the US, even if it could result in capital punishment but may simply not be aware of some law on the matter.
4) The only indication that Assange may ever be extradited to the US is a refusal by the Swedish government to rule this out entirely. This is not a surprising position.
Let's imagine I want to sleep on someone's couch. They say I can only do so if I absolutely promise I will not report them to the police. I'm probably not going to make that promise, or at least not make it and mean it. There is always the possibility that there is some crime serious enough that I will want to report them.
In this case Sweden (and the UK as the nation he was extradited from) would be subject to a genuine and legal request for extradition whether they had made such a promise or not. Were a case made against Assange, given due process in Swedish, British and European courts and found to be valid there is no legal way to block it. As such Sweden is not free to make such a promise. At the same time none of what I wrote above is false; a valid case would require guarantees of human rights and no capital punishment. As such Assange is deliberately conflating two issues; a guarantee he won't be extradited to the US (legally impossible) and the idea that extradition to the US from Sweden would result in human rights violations (also legally impossible).