Terrible me...I forgot to mention Portugal. Both Lisbon and Porto are great. And, if you can make it, a day trip to Obidos is just incredible! And, obviously, Germany. Welcoming to visitors all around. Bavaria, anyone?
Afaik, all we have are those smaller ice rinks during the Christmas season, so we’d have to build something suited to international competition, but that shouldn’t be a problem.
It would be great if an event like this made figure skating on ice popular enough a major club would want to build and maintain a proper semi-permanent ice rink and develop the sport in this country.
As for foreign countries, Spain would be very convenient of course, especially Madrid, Barcelona or Galiza. I’d also love to attend a GP event in Poland or some other country in Central Europe.