I'd second (or is that third) that. For the past 5 years I've just about averaged more miles in Europe than in the UK.
There are some fantastic roads in the UK, but if you're prepared to invest a few quid in petrol, a Euro Tunnel ticket and two extra half days, then you're within reach of some brilliant roads with far less traffic. Last February we had a 6 am start and we were on some great roads in Wales by 10 am. Add two hours on to that and you could be in the Ardennes. In October I left the house at 4.30 am and I was on some great roads on the way in to Trier in Germany after stopping for some lunch. It normally just costs a couple of hours and a tank of fuel extra, and getting up a bit earlier.
We're not going to Europe this year for our main trip, as we're keen to do the Atlantic coast of Ireland and the NC500, but we'll still fit in a couple of long weekend trips over to Europe. I just wish Spain and Portugal were more accessible.