TRy setting max FPS down at 25 and reducing a few other "tasks" on Vancouver. This was something we had in Beta testing - the best compromise appears not to crank FSX as far as she'll go, but to give the hardware more draw time for distant objects.
The blessed trouble is that there is no one common version of FSX - even on identical or similar rigs.
Here's one on my rig taken on the fly - I have maxed my autoge_trees and autogen_buildings to 1500 each.
I am flying at aroound 20 FPS - silky smooth. Yes, i can hit 40+, but the refresh rate is poor.
Also - try using one of the configs supplied with VancouverPlus X - the 30 cm version is for rigs with oomph, but the 1m resolution texture is fine for overflight and allows plenty of spare processor time for distant objects.
