It could be done like in Germany without the spirit of the Senate being lost. Something like 2 representatives plus some number that depends on the population.
It's not the same. The House of Representatives is intended to represent the people. The point of the upper house is to represent the States. There's no reason why there shouldn't be some weight thrown in based on some objective criteria like population.
The way it works in Germany is every Lander has 3 seats; they then add up to 3 extra seats based on the population. This over-represents the smaller states too, but not to the point where small states can block the whole country like in the US Senate.
So, of course my comment was tongue in cheek, but not completely. In order to get states to agree to unify, they had to give them incentive in representation. Remember that Germany is the size of a US state. It would be more akin to trying to unify all of west Europe as a country. Would Denmark join if they knew they'd get zero representation based of population?
The European Parliament assigns seats to member states based on population, but the European Council gives one vote per state. So the answer is kind of -- they basically did join, in spite of odd representation mechanics. And FWIW I think the Council (and its majority voting rules) is as much in need for reform in this respect as the US Senate.
As a German, this makes me wanna cry. The eastern part has taken over the published opinion and political culture after the reunuification, even though formally the eastern republic dissolved while its states joined the western federal government
