I do not have the Danube barge costs at hand but most of the major traders have based their silos on the Danube. I am not convinced that the investments are that wise - I think that they are buying into the old socialist-era belief that the southern plain is going to be a major commodity production area - I have my doubts because of the rainfall and the viability of rehabilitating much of the socialist-era irrigation. There are also soil degredation issues.
That then leaves the question of shipping costs for grains out of those areas where it rains. My view has always been that they will be too high because of the geography. Grains in those areas should be processed or fed locally. The livestock industry has not yet got on its feet so their is little local demand. Net result is that in the natural-rainfall areas the markets are limited and there is no real investment in storage. Overall too much 1985 thinking still in the system.
As to the overall EU payments situation, I came to the conclusion that one-size-fits-all is not the right approach and more needs to be managed at the national level. This I posted a month or so back. It appears that the House of Lords came to a similar conclusion.
Romania's needs are much different from the UK with respect to agriculture and as you say the delivery of public goods is also going to differ. I would, however, suggest that with some of the environmental measures we could consider an EU wide system with respect to environmental areas of global/international importance, just to ensure that the management of these are under the eyes of a wider audience. There are some real hot-spots left in Europe and these are not necessarily in countries where awareness is as high as it could be. The majority lower value areas should be nationally managed.