T.F.
I ook a lot of travel for our copany business as well as personal travel. I NEVER ever go through discounters because those tickets are the first ones bumped when there is an issue. Also, there is no support for you at the airport if you have issues. It is not worth it to us to have that kind of problems when we do have business deadlines to meet. Of course we are more flexble on personal travel.
That said.. I workdrectly withthe airline websites that we use all the time. Mine are American and Southwest. You CAN find deals on their websites if you look. Also, you can plug in flexible dates and it will show you the pricing so you can choose the date best for you with the price.
I know it is not Europe but I fly hubby from Dallas to Houston at least once a month for less than $120 and it all is factored on WHEN I make the purchse.
I don't have a "need" for an agent but there are times that it might be worth it if you are looking for something specific and if you are not accustomed to working with the airlines and websites often.
Good Luck and have a great trip!