Example of a high standard for BBC 2/3 [http://www.bbc.co.uk/programmes/p03ply8y]
Some advice on pitching: 2 or 3 ideas are fine. Conveying a passion for the story you wish to tell is more important that if the pitch is a powerpoint or document format. ‘Back one horse’ don’t send pitch to all the commissioning editors [if one turns it down the others will know about it in their meetings]. Send to one Editor, if they say ‘no’ then back off. Can also send ideas in an email to Editors based on an article in the paper that you might think is a story worth telling. They can respond before you go into making a treatment whether or not its something they are interested in broadcasting.