If you had a digital recorder like the Tascam 2488neo($600-700) or one similar, you could run 8 channels through it, using it's preamps, record 8 different tracks and send a stereo line out to the PA.
After tracking you could load the tracks into your computer via a usb port and mix there or you could just mix and master in the Tascam. The killer is that 9th track you need. You might get away with just 2 drum mics, an overhead and bass.
This is exactly what our band does to record. We use the Tascam 2488 MKII with each member in a different room of the house (for isolation). All the mic cables feed back to the Tascam, which outputs to headphone amps for the members to monitor themselves/rest of the band.
Then, after we've recorded, patched where necessary (the beauty of using the multitrack recorder), and agreed that all of our parts are correct, I transfer the .WAV files for each track into CuBase 4 LE for mixdown.
I don't think it matters what multitrack brand you get, as long as it has enough channels to handle what your application demands.
If you don't have a place big enough to separate into different areas for isolation, perhaps a multitrack that only handles 4 simultaneous inputs would be sufficient. You could record the drums to 4 tracks first, then import them to CuBase. Either in CuBase or on the multitrack, you can mixdown those 4 tracks into a stereo pair for playback for the next instrument(s) recording.
Each time, take the new tracks recorded into Cubase, and add into the stereo mix for playback monitoring while recording.
A bit slower process, but just as good. Also, the nice thing about the multitrack recorders versus the PC recording, would definitiely be the reduced latency.
Good luck!