Nice strat. The Mortar HT is indeed underused.
Have you tried the "old" In before the blitz Airborne strat recently?
What im missing in this strat is sight. Its crucial for 50cals, Scot and Jacksons. Also dont like putting zook on riflemen.
Try this Airborne build in them 2v2's:
Pakhowie or ATGUN (optional, when floating shitloads/situational)
Put double zooks on RE (get minesweeper first so they are hidden) and Pathfinders. BARS's on Riflemen
When your Stuart is alive when Scots hits the field: swap crews. Keep Pathfinders with zooks near scots to spot and protect. Vet3 pathfinders with zooks dont miss btw
Also dont forget to use supervise with captain to rush the Stuart and the Scots.