Painting the ground with textures are one thing ... tugging up and down on the terrain grid squares corners is another thing ... Placing twees, gwass, and schwubbury is another thing.
Creating a DEM using Transdem is a whole different ball game, and can be quite entailed, aquiring topo maps and georeferencing coordinates on them, as it is not for Dummies (as I should know, as I is a functional dummie) ... Using a DEM, the DEM will control YOU ... as opposed to flat baseboards, YOU are in control the route ... If someone creates a DEM for you, you will find that the gradients are a nightmare of a +5.78% gradient, followed up by a -9.87% downhill gradient, a real roller coaster of terrain.
I find that painting textures such as Forest1 and Forest_1, quite effectively replicates dense forests, on distant hillsides, especially when you rotate the textue to show right side up (as opposed to upside down, or canted sideways).
Using the KB keys: [, or ], you can smooth and smear textures into a blur. You can use the scale set a maximum, or minimum, or anywhere in between ... and set the radius at small or large ... You can dab on a subtle splotch of rock, on grass, by gently tapping the mouse, instead of wildly slathering on a heavy coat of texture paint.
I can give you all the tips that I know of
This is all textures, gently tapped on, overlapping each other at minimum radius, and minimum scale:
The year is 2017...Work has commenced at tearing up the Horseshoe Curve original trackage, in lieu of the new quad tracked 5.5 mile bore through the mountain. The Tunnel Boring Machine has just broken through the mountain at Kittanning Point. An overhead electrical cantenary system will be installed, making high speed PRR-TGV passenger service from Philadelphia to Chicago a reality ! Tracks 2 & 3 have already been removed, and the ties will torn up next, and the roadbed will be re-graded as the Horseshoe Curve will eventually be replaced by a Rails to Trails bicycle path, suffering the same fate as the Muleshoe Curve.
The Electrification of the Horseshoe Curve has made high speed TGV traffic from Phila to Chicago a reality !