OK I'm getting the hang of this now. Eames, and anyone else who's yet to give it a serious go, every single bit of info you could possibly want is available somewhere. Along with the map data covered in my previous post, there's also the buttons running down the left of the screen, like HQ, roster panel and so on.
The HQ button is brilliant. Its first tab shows you what you're spending your money on each month, and where it's coming in. A balance sheet, essentially. At first I wasn't sure why I was running at a loss until I examined this, and realised that my best bet for improving cashflow was to make more money on the buses (I only run buses so far) and spend less on wages. So off I went to another tab on the HQ screen, Company Policy. You can set all kinds of options in here. I used it to reduce my drivers' wages a bit, increase the wages of my inspectors (to make more money in fines) and increase ticket prices. At the moment the economy is booming so people have more spare cash to spend on travel.
Everything has associated data that you can examine. Click on a vehicle in the world, for example, then click the little clipboard that appears on the camera view, and you'll see how much money that vehicle made last month, how much was spent maintaining it, etc.
Oh, the roster screen is ace too. Within it you can get a breakdown of not only every vehicle and what it's doing to affect your cashflow, but also every stop of every route - how busy the stop is, how many passengers handled, average happiness of passengers using that stop, which line the stop is on, etc. You can even sort the tables by any of these categories!
Thanks to all of that, I've been able to tweak my business so that it's now running £1,000 a month better than it was, all without adjusting a single line or vehicle. Loving this game!