Sorry for asking and putting you both out for what I assumed to be a genuine question.
I'm not saying your question isn't genuine. As your post count is so low, there's not much to get an impression of how much background work you make before you ask for tips. I tend to assume the worst if it's not clear.
Like you said, your late night window will limit your options so you may have to expand your reach to Northampton or Milton Keynes. For dodgy areas, there are websites that have crime reports for areas of towns.
As Finn said, you may get better cooperation if you write some reviews, assuming you've punted in the past few months.