Note that the best contemporary example of a functioning federal democracy with state-appointed federal legislators is Germany. There, the state premiers and some members of cabinet are members of the Bundesrat, the upper house of federal parliament.
As an empirical matter, it certainly seems as if their interest is in increasing federal power, since that gives them more power against their own state legislature. If they want a bill passed, they can use their federal power to create an obligation on their state parliament to pass a bill.
Consequently, the very clear direction of power shift in Germany has been - much more so than in the English speaking federations - an increase in federal power. (Also, a more recent prohibition on state deficits even accelerated that trend. State governments became enthusiastic about trading a little power for some extra money.)
When, as in the US, state lines run through the middle of metropolitan areas, cities and even small towns, and generally serve more to divide than to unite, it is not at all obvious that an increase of federal power compared to state power is such a bad thing. I think it would be better to redraw the map and then for the states to have powers that make sense. But I think that is about as likely as a Democrat and a Republican to agree on the color of the sky on a clear day.
> As an empirical matter, it certainly seems as if their interest is in increasing federal power, since that gives them more power against their own state legislature. If they want a bill passed, they can use their federal power to create an obligation on their state parliament to pass a bill.
You already explained the reason this happens in Germany:
> the premier has an interest in transferring power from the state governments since their power as a member of the federal upper house is greater than their power as a member of the state lower house.
Solution: Don't put the same person in both houses.
> When, as in the US, state lines run through the middle of metropolitan areas, cities and even small towns, and generally serve more to divide than to unite, it is not at all obvious that an increase of federal power compared to state power is such a bad thing.
State lines that run through the middle of metropolitan areas are the best kind, because they give people the greatest choice. If you don't like your state government and voting hasn't gone your way you don't even have to move across the country to change jurisdictions, only across the street.
Moving things to the federal level does the opposite. Things haven't gone your way? Too bad, there's nowhere to run.
The Premier of a German state is also the head of majority-party in the state legistlature. Also, they are sitting members of the state legistlature.
That being the case, state prime ministers have a huge amount of power and influence, directly through mandates and indirectly through party politics. And usually, they want to to retain the maximum amount independence for their states.
And as far as federal legislation is concerned, one state prime minister is not enough to pass, or trigger, anything by himself. For state legislation, they don't have to pass through the federal goernment anyway, holding the parliamentary majority anyway (minority governments are extremely rare in Germany).
As an empirical matter, it certainly seems as if their interest is in increasing federal power, since that gives them more power against their own state legislature. If they want a bill passed, they can use their federal power to create an obligation on their state parliament to pass a bill.
Consequently, the very clear direction of power shift in Germany has been - much more so than in the English speaking federations - an increase in federal power. (Also, a more recent prohibition on state deficits even accelerated that trend. State governments became enthusiastic about trading a little power for some extra money.)
When, as in the US, state lines run through the middle of metropolitan areas, cities and even small towns, and generally serve more to divide than to unite, it is not at all obvious that an increase of federal power compared to state power is such a bad thing. I think it would be better to redraw the map and then for the states to have powers that make sense. But I think that is about as likely as a Democrat and a Republican to agree on the color of the sky on a clear day.