I love the hop selection. Seems like most recipes are for American versions, but I am a fan of a more traditional Brit version. I might only suggest two changes. You could add 50% to both the roasted barley and chocolate malt. Also, for fullness I would get rid of the lactose and get that from a grain such as Munich or Melanoidan instead.
Kegged: Belgian Dark Strong, Robust Porter
Next Up: Ryewine
Projects: Freezer Conversion (Done), HERMS (Done), Lager Fermentation Mini-fridge Extension (Done)
Drinking: Great Lakes Edmund Fitzgerald, Fuller's 1845, Lakefront Fixed Gear, beers from SAVOR