Forget everything else - it's just the bail jumping.
Assange broke the terms of his bail which were issued under UK law, and that's what he will stand trial for when (and if) he finally leaves the embassy.
Anything else is a sideshow.
A pragmatic person might ask why the UK didn't get a formal undertaking from the US that they would not seek to extradite Assange once he was in UK custody (possibly being then passed on to Sweden) as that would have removed the excuse which Assange is hiding behind.
1) WTF should they ? Assange is wanted on suspicion of a criminal act. Generally the UK doesn't treat with such people (unless they run a country)
2) How ? The US could quite rightly say that they have never sought to extradite Assange (which is embarrassingly the truth); or they could correctly say that they do not issue statements about ongoing investigations.
3) The fact that Assange could not be legally extradited on from Sweden without the UKs agreement. Which would not be granted as he has to stand trial here first.
His most serious error of judgement was to do something which makes the courts look stupid. Offences about justice are (rightly) considered very serious, and always attract the severest penalty. Otherwise any Tom Dick or Harry would just jump bail and cock a snook at the beak. And that would never do.
The way things are going, it'll be President Winfrey issuing a free pass to Assange. I wonder what excuses he will have then ? That the entire US election of a sympathetic president is really a CIA plot to "get him" ?
Assange and Farage. Two people who seem to need the limelight.