Most English will compliment a good scotch and will bring out the sweetness that can be hidden in a nice speyside or round out the harsh notes in an isley. A traditional Scottish mixture is an English that introduces a good brown Cavendish or black steamed VA Cavendish. 965 could be an example or G&H Scottish flake. Rattray's is a Scottish brand, though no longer blended there, and I find a dark Va also pairs well with speyside such as Marlin Flake or Wessex campaign. They have Scots blends as well but I haven't tried them.