The obvious and probably most controversial way the European Parliament can become more powerful is if national parliaments were to give up more of their sovereign powers to the European Parliament. For example, the European Parliament is weak when it comes to foreign affairs, as it has little to no real policy in this area. This was seen when some nations participated and others refused to go to war with Iraq in participation with the USA and a stance form the European Union, and in this case the European Parliament was not forthcoming. There have also been previous flirtations with the idea of creating an EU army, but there is too much opposition from within a number of nations to give up sovereign powers, and countries may not want to commit to such excursions. Of course in Britain, there is intense opposition and scrutiny toawards any such measure taken by the government of the day that would infringe on any sovereign powers being transferred, with tabloid headlines fearing a "Rule by Brussels" as it were.
However simpler and less controversial measures can be taken to create a better European