I have never been one to spend hours on my bases as I prefer to get on with the figures themselves. Saying that though, I have been influenced over the years by what I see on other peoples Blogs. My bases are a mix really of both speed and detail.
I like the look of sand and grit of American bases as it sums up the atmosphere nicely of the Americas. However, I don't want to spend all day sticking and painting.
The happy medium for me is to just stick small areas around the base with sand then flock the rest with static grass. The effect is the same as covering the whole base with sand and then flocking but in a fraction of the time. Clumps of grass and small bushes finish off the base and bring it up to collectors standard very quickly.
Job done on to the next...
A partly sanded base, this will be painted and dry brushed to add detail. The rest of the base will be flocked with static grass. This way a big unit can be completed very quickly and still look good.