how do you approach creating house drum patterns?

[BiggChev]

In the later versions of Cubase you don't have to worry about CPU load because the DAW automatically converts to a temporary audio track. You still have your MIDI channels there but for the sake of playback it's treated as audio.

I bounce down to audio simply to reach a certain level of commitment. This way I'm not tempted to go back and tweak drums. Like I said I usually dedicate time to solely doing drums/perc.

As for my fills, it really depends on the groove and overall feel.

Datsik has said in a few interviews that bouncing to audio really keeps his workflow moving as he "Can't" go back and make adjustments.

[Polygon]

As chevv said, it's because i tend to leave things unfinished, so committing myself to finish part after part in the end gets the track done better than procrastinating around with millions of things you must fix bugging you all over the production.

[dtrostli]

Check out the Nerve plugin by Xfer Records. I use it on every single one of my tracks, I've found it to be the easiest and most versatile drum programming tool. I'm pretty sure there is a free demo available.