Re: @Arnaut the less
" Improve the M5 and the M6."
Too late for that, mate. These roads are now at capacity, and widening the carriageway (or hard shoulder running) can't make up for the peak capacity limits on junctions and feeder routes. When most of the current motorways were designed there were about 12m vehicles on UK roads. There's now 34m, and for the most part we've added at best 33% to the motorway capacity.
Notwithstanding the recent (probably misleading) government claim of billions of new money being spent on roads in the next few years, we've got a fast growing population that will add another 2m vehicles to the roads in the next five to ten years. If you wanted to improve the road traffic situation then the only way would be new roads duplicating important routes. Can't see the Welsh Marches being too keen on an M5/M6 relief motorway parallel to the A49, for example.