I for one would love the 'option' to taxi out prior to take-off, but I think the only way to get that now is to use a mission builder and place your aircraft on the ramp or in a hanger.....which I dont think is what you've got in mind....me neither
As for the scenery, I personally have the Black Sea Terrain, Southern California, and American Northwest(Oh ya, and the Range).........the only time I fly the stock terrain is in campaigns. All of these terrains are much more entertaining to fly in than the flat pancake also known as Duetchland I am still using the original woe but I think all these terrains are useable in the new series??? As for campaigns with these sceneries, there are a few to choose from, none of which I have tried.