Spacers or fixed charms will do what you want...
Also, if you don't want to fork out for the Pandora charms, have a look at other jewellers charms and the cheap ones at markets etc... although they say you shouldn't put them on, I have done it and it doesn't damage the bracelet. Also, sometimes they are nicer than the Pandora ones
But, as Briggy's Girl said... subtle hints to the partner