Yes, the two lines on the left would go to the fiddle yard and be the two 'main lines' coming in to the layout.
I have played around with it and put the cross over in as you suggested, I have also taken a little length out of the station lanes which gives the layout a more balanced feel in my opinion.
I would also like to introduce another siding on the bottom left, which could be for loco storage/fuelling/washing etc.
I have some more points/track on order and I've treated myself to a DMU!
Thanks again for the advice and I will update again soon. I will research the layouts you mention as I'm sure they will be of interest.
Regards
Mark