Given that the BBC accounts for what...5 or so channels out of 500+ i fail to see the value. Ok, the quality is better than a lot of channels, but it is still disproportionately expensive.
Those last 5 channels out of hundreds upon hundreds being commercially funded would have zero impact really. If you dont like adverts then just watch as its best to watch all channels, on a timeshift allowing you to FF the breaks.
The BBC's 5 channels in the average day produce much more (proper*) new content than between 10 and 100 of the of the other channels (depending on if you're including Sky 1 on a good day, or just the dozens of channels showing repeats**), excluding the premium sports channels (and that's ignoring the News Channel, Parliament, the Radio stations etc).
It's also worth noting that statistically BBC 1 and 2 are the most watched pair of channels in the UK, even in households with full Sky/VM packages.
So, 100 channels of mainly old repeats (some showing the same few episodes every month for years), with very little UK content, of 5 channels showing primarily new content, most of which has been made specifically for the UK market.
Guess which costs more to do?
Seriously if you want to see how much value a lot of pay packages give, in terms of new content go through the listings some time and have a look at the repeats.
BBC1 alone averages about 8 hours of new content a day (sports and news excluded), Sky 1 on a very good day manages 3 hours, usually less than 2 hours, and Discovery is lucky to average an hour a night of new content
*As opposed to the likes of Bid UP TV, and QVC which could be argued to be new content, but is basically just long adverts
**Many of which were originally produced by the BBC
