I'd say Scotland and N Ireland have as much self goverment as states in most federal countries and even if they don't, the level of autonomy that they do have would still do very nicely for England, thankyou very much.
Autonomy for whoom from whoom?
The UK Government is so dominated by English Representatives that it is essentially an English government.
The Northern Irish Representatives are roughly evenly split between the major parties and don't normally do anything that could bring down a government.
Meanwhile, despite Tory rantings, there has not been a recent election result that would have been changed significantly by Scotland being independent - you would have the same government we have now.
And Wales is so small that it has little impact on anything.
So you concede that the difference between West Germany isn't one of practicality, rather one of history. I believe that the future is for us and our descendents to decide. Afterall, who, forty years ago would have thought that the Celtic home nations would have as much autonomy as they have now.
No, a traditional German federal system is now impractical in Germany - it is just slowly realigning towards to the unitary model. Just because it is less far down this path than us (due to institutional and cultural inertia) does not mean that we can go back to that model reasonably.
And considering Northern Ireland has been self governing virtually since 1922 apart from the Troubles causing problems, and the Scottish had just voted on a devolution referendum in the 70s that was rejected by a
tiny majority - I imagine people would not have been too surprised by the level of devolution that has occurred in recent years.
There will be tensions between levels of Government in any federal set up. The states in the US and the lander in Germany still have a lot more autonomy than us.
This is a result of historical inertia and is slowly being crushed - the US states have an advantage that it is not normally possible for the entire population of a state to
commute across state lines - they are far larger and thus the damaging 'edge effects' of changes in taxation become less significant.
The rise of online shopping is likely to increase this effect as distribution centres for deliveries can be located near motorways in the most tax efficient locations.
Our regions might need some tinkering, but I've no doubt that Yorkshire could step up to the mark.
Assuming people will even go in for Yorkshire, which everyone not in Leeds is likely to see as Leeds boosters attempting to make off with all the development money they could keep themselves.
Would York or even Sheffield submit to what amounts to permanent rule from Leeds (due to census voting)?
Or Liverpool submit to permanent and eternal rule from Greater Manchester?