Took a notion and decided to start scenic work on one corner, I'm happy with the trackwork, fully tested with Steam, Diesel, DMUs, Coaching stock, and twin axle and Bogie freight, all running smoothly.
Trying to construct it to look like the branch line was there originally and the main lines were added after, with an older stone style bridge transitioning into a more modern plate girder style bridge and a cutting to allow the two main lines to pass through.
Raised section was built from offcuts from my first layout attempt and packed with insulation foam, followed by expanding foam and cut down to suit.
Bridge is a hodgepodge of wooden offcuts, clad in foam board and plasticard, waiting for Slaters embossed plasicard to make it look more bridge-ey. I'll have to get more embossed plasicard and foam board to create the cutting walls before using Sculptamold to build up/fill areas before plaster being applied to lock it all in.
Thanks all!