I have the feeling that you are rushing it a little. As I believe you have not included time for travel, some of your stops will be too short in my opinion. If you can't see everything in one trip, than don't be too afraid to make the choice to save some places for a later trip.
I think the UK & Ireland trip is OK, although there is more to see, especialy in Scotland. (think Isle of Sky, Fort William, Glasgow) It will make a good first exploration of this area.
I would switch Brussels for Brugge, esp. I you are gonna stay for only 1 night in Belgium
4 days in Amsterdam is more than enough (in my opinion 3 would do, unless you want to visit a lot of musea), and it would be enough to see Haarlem as a daytrip. So I don't see the need for the 2 days in Haarlem. If you are traveling by train to Berlin. I would recommend seeing Groningen instead of Haarlem. Another option Could be Maastricht, from there you can travel to Cologne or Duisburg for connections with the train, or to Cologne or Düsseldorf for a flight to Berlin.
Personaly I would skip Warsaw. You need time to get to Krakow. (try a flight. If I am not mistaken Directfly has direct cheap flights to Krakow). Also to get from Krakow to Prague will take while. It looks pretty close on the map, but it's a mountainarea so it takes longer than you expect (see
www.bahn.de for timetables, go to international guests)
Prague, would need 1 day more in my eyes, and Vienna needs at least 4 days. Again Zürich would not be my choice in Switzerland. It might be a nice city, but think Switzerland, for me would be thinking Mountains! Interlaken would be a nicer stop in Switzerland. You could also opt, for getting to Innsbruck in Austria, which is also a city with a nice scenery in the mountains, it's cheaper, closer (in traveling time from Vienna), and it would open up the possibility to go from here into Italy first.
Unless you need to see the Last supper and/or the Duomo in Milan, than I would skip Milan to make Venice two whole days, and add one more to Florence. (I see that Point ... made this point already)
Getting to Greece for just one day, is ludacris. I would save it for a seperate journey somewhere in the future. The city needs 3 days, and when you made it that far I would also get to some of the Isles. The same is true for Reijkjavik if you are gonna make it that far up north, than take the time to explore a bit more of the Island, than just the capital, which is nice, but not nearly as spectacular as the wonders of nature on Island. I know there are flights going via Iceland, so if you are planning one of those, and you can spend a day in Iceland. I would take it, but more days would be recommended here.
The time you need to travel from Switzerland thru Caen, via Lourdes to Madrid. Is way too long to attempt on such a tight shedule. The bus from Tarbes (close to Lourdes) to Madrid already takes around 8 or 9 hours. (my friend in Madrid had a girlfriend in Tarbes, and I recall a nightbus, which takes all night to get there). You can take that bus. But it would be too much after already spending most of the day, getting to Lourdes. Maybe take a few days in this region. There is enough to see in Lourdes, and a daytrip to Tarbes can be nice as well.
Madrid in 3,5 days is possible, and it would be enough time to also visit Toledo. (if you want to see a little of Toledo, watch the film Te doj mis ojos, (Take my eyes), which is filmed in Toledo).
If I am not mistaken than Fatima is in Portugal. Which again would take most of the day to only get there. As with Greece and Iceland, Portugal is also a country which deserves a little more time, than just a rushed visit to Fatima. 3 days in Lisbon would be nice, and depending on the time of year, you could have some relaxing days in the Algarve (Lagos?)
I also have to say, that Spain has more to offer than just a quick visit to Madrid. I love the city but there is much more to see: (Barcelona, Granada, Sevilla, Cordoba, San Sebastian, Santiago de Compostella).
I know you are interested in Catholic sites, and I think that Santiago is easier to reach then Fatima or even Lourdes, as it has a airport very near with a couple of budget airlines flying to this airport.
I short:
I would think of skipping Greece and Iceland (too much effort and costs to make it worthwhile for just one day). Also skipping some other places, and add days to cities that now have too little days.
I know that you can run out of days, when you try to plan everything into this one trip. You could consider to cut off the UK/Ireland trip. And save this for a 2-3 week trip in the future. (and maybe then see a bit more of Scotland). Or consider skipping the Spanish/Portugal trip, and also save this for a longer stay in the future (and adding the other towns I mentioned earlier).
