I'd turn the BBC around completely. At present their main objective it to try and "out do" ITV - present the same kinds of programmes ('cos they're popular, innit?) but better, glossier, more expensively, with more celebrities and without advertisements.
So we have the situation that when ITV screens a soap, BBC does the same. When another channel has a news broadcast, same on BBC1.
What I'd do is have the BBC channels provide alternatives to the commercial channels. Not alternative soaps, sports, documentaries and game shows but different genres all together, That way viewers would have real choice: not just whether to watch a game show on ITV, Channel 4 or the BBC, but to have something completely different on, instead.
So there would be more programmes from and about the regions of the UK (but broadcast nationally) and MUCH less sourced from London, more minority interest programmes: such as maybe a half hour slot for stamp collectors or knitting (in the vein of The Sky at Night). I'd have 3 hours every school night for homework help on the childrens' channels, and long-term programmes about less popular sports: such as sailing, hockey or running - maybe with an emphasis on getting women to take part in more sports. Also late-night access for up and coming bands, comedians and other live acts (but with no voting or audience participation - that's so ITV!).
Sure, the ratings would be lower for this type of programming but the production costs would be smaller too - without multi