Thanks Colas - that's good to know because I assumed more volume = better performance in choppy conditions & I didn't realise your point about width at both ends also assisting......which makes sense. I figured less length would help because my Laird tends to nose dive the minute the chop is significantly up.
I'll save your reply whereby if my other half decides she reallt can't manage my Laird (she's 55kg so the length & weight is a concern for her....although she's only ever out in clean conditions) I can then consider the board options you mention. For the time being, I'll crack on with my JP