Re: End of justice
It should be noted that juries are far from perfect. Jurors have no legal training, they're subject to all sorts of biases, prejudices and external influences (social media, I'm looking at you) and, crucially, they're not required to explain how they reached their verdict. Whereas a judge or magistrate has to provide a written explanation of their decision, making it much easier to appeal, should there be a problem.
Also, if an offence carries a three-year sentence, that three years is the absolute maximum given by the sentencing guidelines, and almost all defendants will receive a different/shorter sentence, depending on the circumstances of the case.
The jury trial is undoubtedly a good thing, but I don't think the proposed changes are that bad, and if they reduce the time (sometimes years) that defendants hang around on remand, then justice may be better served.
Introducing AI, on the other hand, is a terrible idea.