A little while ago this blog argued in EU: Enlargement fatigue? (1 April 2009) that the Lisbon Treaty may be an improvement compared to the Treaty of Nice, but it does not create an effective or democratic union.
In my opinion, the main fault of the French and German governments is not that they put a brake on EU expansion, but that they do not envision reform beyond the limited Lisbon Treaty.
EurActiv’s 17 April 2009 interview with Erhard Busek illustrates the problems: Busek: Western Balkans should join EU as a block.
Busek finds that it is now difficult with 27 members to come to decisions: with 32 or more it will be even more difficult.
If the countries of the Western Balkans accede, their number of votes in the Council and the number of MEPs will be much greater than their proportion of the EU population.
Busek names this as a problem. But he sees that in this way, pressure is created for changing the systems in the European Union. Personally he is convinced that the current voting weight repartition, as well as the lack of qualified majority vote in most of the situations, is the real background of these hesitations. It has nothing to do with region, because it's completely clear for all member states that all the Western Balkan countries should become members of the EU.
The Busek interview underlines the need for effective decision making and it at least touches upon one important aspect of democratic and fair representation, namely with regard to population numbers.