Photinia is a very lax and open plant, 2gb. Plus it is sloooow. Not good for N facing tho.
Berberis is not a favourite of mine, but will go UP quite quickly, not expensive and has added advantage of nasty little pricks on it. Similar to what you have at the moment : ) thunbergii .. purple ... if you must.
Laurel, Attractive, dense, ok -ish for N facing. about 3-4 years tho to fence height from 1ft plant. but needs care and regular cutting with age. I just cut a 30M laurel hedge today for family .. tiring.