Nurture a love of learning, of meeting new people, of trying out a new language (DS was bonjour-ing for months after we got back from France!).
For our 8yo he loves:
Wild swimming - looking for fish with his snorkel, seeing frogs, he remembers insects that skip across water fondly, watching someone's flip flop floating down the river!
Interesting ice cream flavours - his favourite is violet, tried at a little medieval watermill from 1096, fascinated him.
Walking up a big mountain surrounded by cows and waterfalls, he also saw a snake.
Simple campsites where he can ride his bike and have adventures with other children, plus he likes sleeping on the floor, playing Uno and eating sausages outside.
Walking in the woods and building forts out of sticks. Better if there's a picnic site.
Very rarely do we do big expensive day trips out - zoos etc.
He has friends from many cultures and he loves other languages, I think that'll carry him well through life.