For keyboard we have Roland A-90 with it's 4 midi outs plugged into an old MOTU 8x8
Midi TimePiece/switcher-router. We have a handfull of externel synths tied into the the
motu also. The motu MTP-AV is connected to the computer via the parallel port.
The external synths' audio is brought to the computer via a combination Mackie CR-1604
and Delta 1010.
We also have an old Peavey PC 1600x midi controller and a Roland SPD-20 drum pad that can
be patched into the system when needed.
All of the above works pretty well through Qjackctl(10 audio ins, 10 audio outs, 9 midi
sources and 9 midi outs when needed).
I just got a m-audio Trigger Finger(usb) that I'm starting to learn to use. I can see
that fitting into the system sometime.