Re: What's wrong with my telly?
"I loathe the Sky and Sky+ remotes. Too many buttons. Not obvious how to use them. Difficult to use in a darkened room. The pause/ rewind etc. is good but not unique now. For me, a context-sensitive touchpad on a display like an iPod touch/ small Android tablet/ smartphone would be an improvement..."
Although I haven't got one, I've seen some Logitech Harmony remotes that are backlit and I believe customiseable with touchscreen displays which might do the job.
I've used my Android phone to control Blurays and I there is a MythTV app for Android and iPhone but I'm loathed to buy a mobile phone to use as a remote (or leave my mobile at home so the rest of the family who don't have Android phones or iPods/iPads/iPhones can change the TV channels).
"As for the TV broadcast standards, it is sad that there still is apparently no seamless way to make sure the correct picture aspect ratio is correctly applied. Why isn't there a place for this information in the standard? Maybe there is, but it is not implemented very well by either TV sellers or set top box sellers or the broadcasters."
Works fine for me, IIRC Widescreen switching is part of the standards. Not sure how it does it over HDMI but in the SCART days it would do it via a connection on the SCART cable. Maybe it's a setting not set on the device. Never seen any problems myself switching between 4:3 and 16:9 on various boxes (Freeview boxes, OnDigital box, Sky boxes).
"Do the standards allow the BBC to interleave different streams of their own (video and audio channels)? Why not?"
I gather that DVB does allow for different audio tracks although I've not seen any programmes with alternative audio streams on the BBC, although I gather that it's possible to include an audio description stream. I remember in the old analogue satellite TV days you could get radio channels on some of the TV channels by just changing the audio settings (IIRC each channel had 2 or 3 audio tracks).
"Or the end user to do the same? Why not?"
You should be able to select which audio stream you want, assuming they are broadcast with the video.
"Since I get lots of TV channels and radio channels through the same pipe to the same set top box, it would be nice to be able to set up a test match with TV video and the BBC Radio commentary.
Why can't I do this?"
Not sure about Cable, but at least on Freeview the radio channels are transmitted on different muxes to the TV channels so you'd need a tuner for each mux. Technically it would probably be possible maybe with a dual tuner box, or a box of some sort connected to the internet (Youview box maybe) which could grab the radio stream and play this instead of the normal stream. Or the Beeb could offer radio streams alongside the TV streams.
Maybe there just hasn't been enough call for it to spend time on doing such a thing. Although there's nothing stopping you doing it yourself (maybe grab a copy of MythTV and have a play).
"I expect it's the same lack of awareness of what customers want (even if they don't know it yet) exhibited by the Windows boys, Linux boys and Nokias of the world."
But do customers want it? Just because you want it, doesn't mean the other millions of people in the country are that bothered. I'm sure though you could always setup an online petition to try and drum up support for such a feature, maybe there are millions out there who want such a feature that are all sitting there grumbling about not being able to do what you suggested.