I have only had Sky for a few months but believe me it is the biggest waste of money
ever.
Most of those channels are just repeats, there is endless repetiton or simply foreign versions of UK shows, for example, we've got More4 which airs Wife Swap USA, so instead of crazy British families you can see the American ones, there is nothing new to watch. it's just dressed up a little differently.
Honestly even having those extra channels I rarely go beyond the basic channels I had before, and like you said the BBC isn't what it used to be or what it should be, like I said the news is about it for me, maybe a documentary but the BBC is sadly lacking in that department these days as well, apparently Strictly Come Dancing is a better use of the license fee.