This was the state of my studio before I packed up and left for California.
My Toshiba laptop handles all the DAW duties and a hidden 486DX100 works as a MIDI router for my MIDI FX. The laptop can handle more than enough tracks so there's no need to premix anything but I have never pushed it to it's limits.
I'm up to about twenty-two hardware synths and well over a two hundred softsynths and FX. Its a sickness, I know. I am cured, however. I can actually look at a music catalog or go into a music store and say to myself, with conviction, "I don't need anything else." You can't imagine how good that feels.
If only I could afford a real analog modular beasty....
An early version of my studio before I started using my laptop. Note the old 486DX100 and Pentium I, used as a MIDI router and sequencer respectively. Everything was sequenced and submixed; the recorded audio being handled by the Akai DPS12. This of course limited my audio to six stereo tracks of any number of synth channels were being played back live from the sequencer. I think I was up to about twelve MIDI synths by then so I could have as many as 72 "tracks". I don't think I've ever used 72 tracks for anything.