I have only read the 1st page, so will catch up shortly with other posts, and apologise in advance if the thread has taken a different turn now.
I have a friend who is now in the same position as you OP.
She claims JSA, housing benefit, council tax benefit and rents a social housing property (so her rent is not as high as a private rent might be.)
We live in the arse end of nowhere.
If she were to find a job, she'd be lucky to find anything more than minimum wage. She has no qualifications and no experience.
She has been to see various different job centre advisors over the last few years, and has been told that should she go to work full time at minimum wage, she would receive;
£203.73 approxiametely in wages
£10 working tax credit
£28 housing benefit
Total = £241.73
She would have to cover weekly;
£106 rent,
£22 council tax
£29 bus pass for the week
This would leave her with £84.73.
Since current rates of JSA are £71 per week, she is just not prepared to work 40 hours a week, be out of her house (which she loves to be inside of) for an extra £13.73 a week.
I honestly thought she must have missed out on being entitled to more help, but when I saw the breakdown the advisor at the jobcentre had given her, I realised she was right.
I don't know what the answer is. In my friends case, I honestly can't see her ever progressing at work to earn much more than minimum wage if she ever got a job.
And tbh, minimum wage is not always a stepping stone, there are many people who will spend their whole lives working for minimum wage, and I don't agree that they should only expect to be £13/14 a week better off than unemployed.