You say it's a tilebuggy atm, but I don't see any ATM. lol

Jokes apart, here are my suggestions for your tileset to look the best possible:

Some blue diamonds and gold nuggets nudged in the rocks.
Some medieval element such as weapon shacks, chests, herb shacks, armors, thrones and banners upon those bricks. And ofcourse, a back wall made from draker, bluer bricks.
Some warped oaks, willows and birches, and ofcourse, pines or spruces. Some of these are composable like the spruces in Diamondus.
Some iron fence with barbed wire and some alarm light on the top, and some turret and radar.
Some modern military elements, such as hangars, training camps, runways and whatever comes in your mind.
Water pools, not like the water in the Beach levels, but like the ones in the Jungle level. And a variant to have ice upon the water pools.
Gigantic mesas (very steep mountains) with waterfalls on layer 7.
Some vertical 1 pixel stripes with a random color from 176 to 208 to simulate the giant sun's light rays.
Some giant statues of turtles, rhynos and lizards.
Some crystals coming out of the ground.