Not really. Not because of a powerful computer but the fact that I'm working mainly with audio clips. I'll sample my own instruments and do rough processing of any sound, generally just subtractive EQing and a compression to each individual audio clip (for example the bassline), then I resample my bass sound, 1 octave in the range that I'm working in and then a few longer notes and other variations if I can't replicate those with my resampled bass audio clips. Then I tend to just freeze my tracks and keep them available for later use in case I want to go back and change stuff up.
Then I load up my different samples in drum racks and go from there. I don't do this with every sound. But the rhythmic backbone of the track is usually chopped up like this. And if I then want to mix a little I just leave the insert section of the tracks unfrozen and apply whatever processing I want, leaving the actual instrument frozen. I tens not to use very heavy plugins at this stage because it really isn't necessary at this point, I only mix as I go to get a better feel of what's to come.
Midi is fantastic but there is nothing quite like the control you get when working with audio clips.