Well, Buttons I am pleased you have been here and you enjoyed your visit.
Yes there is a lot to see and do, and quite a lot of it is very strenuous so I am not surprised that you feel you overdid it a bit. We are a similar sort of size to the UK but not so crowded!! and without the history which we found so interesting in your part of the world, but it is certainly very scenic and there seems to be a surprise view round every corner.
One criticism has been that some people find that the Camper Van companies tend to move you on too quickly. Sometimes it is necessary to smell the flowers along the way (or smell the sulphur in some places) and if you are too rushed it gets hard to take it all in. Looking at the map it seems easy to travel big distances in a short time, but as you have no doubt learned, our roads are not built for hard and fast travelling.