You can make midi drums organic sounding, but it will take some work on top of the standard copy and paste routines.
In my case, I usually make a standard riff for the entire song, with separate tracks for the kick and snare, toms, hats, crashes, and other percussion. Often, I will use one drum channel, hence one drum kit, but in extreme cases, I will use as much as 4 separate kits (which means 4 separate drum channels) when a particular sound is not working. The reason for the separate tracks is to make it easier for me to add or even subtract notes since having all elements existing in one track can be confusing.
I sometimes make my 'standard riff' quite dense then I will copy and paste it along the entirety of the song. I then proceed to thin it out during the first half of the song since in most arrangements, the the first half of a song is usually sparse or not as lively as the second half - this creates a sort of tension in the arrangement. I may also program fills in this stage as the mood strikes. For the choruses, this is often a variation of the standard riff, sometimes not; I may copy this to the succeeding choruses and add variations later. While I am in creative mode, this is where I add breaks, additional percussion, whatever calls out to me.
When all notes have been been programmed, I then start with velocity variations (do not use ANY velocity randomize function except if you can limit the highest and lowest values). This is often where I start adding ghost notes. Then I start leading or lagging certain sections to add more tension or lighten up on the feel. Whether I use drum pads, keys or draw in notes depends on what's easiest at the time.
The last part of any intensive drum programming that I do, I will put in 'mistakes'. In some cases, I will remove certain hits or make them just that much off. This is critical in making midi drums sound organic. And there you have it. How long does this take? Anything from half a day to 2 weeks depending on mood.
