Best comment I have heard is that he divided Britain between people who thought he was good at his job and people who thought he was good at his job.
I think he did a grand job of getting his members well above market rate salaries and I'm sure for that his members were happy for him to be paid a pretty good salary. He was a hypocrite mind. His claimed he was worth his salary and his holiday in Brazil was fair enough as he paid for it. Now I have no problem with that per se, I'm paid a reasonable salary (not as much as him mind!) and enjoy holidays in tropical locations, but I don't go around saying "I believe in a society based on need not on greed", that made him a hypocrite. It's typical amongst socialist leaders though that the 'From each according to his ability, to each according to his need ' applies only to other people.
He was no champion of the working class either; he was a champion of his members for sure but all those high salaries he got them for performing basic work made commuting all the more expensive for the rest of the working classes.
He also seemed to not be able to see long term. Work switches from to machines once it's cheaper to buy and use the machine that it is to pay a human to do the job. By inflating the cost of driving tube trains he has simply ensured the switch to computer controlled trains happens sooner rather than later. He might have thought he could postpone the switch with industrial action but history shows that you cannot stop the march of technology.
He was a man who was very, very good at his job and who I'm sure thought he was doing A Good Thing, but he was deluded and a hypocrite. He also said, only days after her death, that Lady Thatcher can rot in hell so he was classless too (unlike Boris Johnson and what he had to say about Crow).