Raising the lens would reduce the foreground and increase the sky. It would raise the viewpoint a little, so that a bit more of the top of the piers would be visible and the left-hand (as viewed) lighthouse would move a little further down from the Abbey above it. All this would be very small. Front rise (from their website) on a Chamonix is 70mm, or about 2½". If any rise is already applied (Ian doesn't say) this would be lessened.
I suspect that the effect would mostly be on the framing. A bigger tripod and a small stepladder would be needed for a radical change. Jem Southam sometimes carries a stepladder.
All this assumes that Ian agrees with your diagnosis. We have no reason to suppose he is not happy with the shot as it is.