I'm about to set off on my third Euro VFR trip in three years. We started with France and Spain, last year we did Holland, Germany, Poland, Baltic States, Sweden and Denmark. This time it's France, Italy, Croatia, Slovenia, Czech, Germany and Belgium.
1) My first trip was as an 80 hour PPL and I had no problem.
2) Mostly I'd say flying over there is easier than in the UK - better service from ATC and less congested airspace.
3) Filing flightplans - you get into the habit. It takes about 3 minutes when you are practiced.
4) Good GPS is a must (for me)
5) Fuel up as soon as you land.
6) Jepp charts wherever you can. It is so much easier when you don't have to get used to different style charts with every country you cross.
7) Bottlang trip kits are excellent. If you want to save you can download most of the info from the various country websites, but it's a fag.
8) Just go for it - it's so, so much easier than you think.