“As it is the jury found many of the defendents innocent which would not have been the case otherwise.”
Otherwise than what? Other than if they had been tried by a jury, do you mean?
First of all, you simply don't know if that would be the case. But, more importantly, a trial by jury is the cornerstone of British justice. The prosecution has to bring evidence that is sufficient to convince the jury of the defendant’s guilt, and that evidence has to be simple enough for “the man in the street” (for that’s what jurors are) to understand.
The alternative you are proposing is, I suppose, trial by judge or judges alone. Criminal trials are already seen not so much as quests for the truth but as intellectual challenges by highly trained and specialist legal professionals. They often have to be reminded by judges and magistrates that their duty is to convince the tribunal beyond doubt in a manner that they can understand. Removing the man in the street from that tribunal means that trials will simply descend into a series of unintelligible legal arguments.
Then what next? “Well, most of the evidence we have is so secret that we cannot disclose it, even to a judge. This matter is so serious that we cannot possibly discontinue the prosecution so we’d better just record a conviction and proceed to sentence”
With some very rare exceptions, trial by judge alone is not the way things are done in the UK. Those accused of serious crimes are entitled to have the evidence against them put publicly before a panel of their peers. If the evidence is not available or not to be made public, then no prosecution should succeed.