We moved to a new house in April and we have a shed load of established laurel.
All "SUMMER!" they've been shedding leaves which are yellow and brown.... now it's not as noticable on our plants as it is on yours, because they are established but I think you should stick with them, there's been so much rain this year I was considering building an ark! It might just take until spring for some new growth to come through and bulk them up.
The other thing we have is the laurel berries dropping and sprouting so we've a second layer coming through busshing up the lower half.