I suspect I'm being talked past, Daniel, but I'll answer anyway. Eight faders is not as good as nine or 16, but it's better than seven, so most people would consider it worth setting up if you're mixing in the DAW. After all, it doesn't cost you anything.

If you do mix in the DAW, things like lowering an 8-bar phrase where the singer was too close to the mic are probably easier using "off-line" mixing - i.e. drawing in the change. But most people find things like riding vocals easier with faders. So motorized control surfaces like the Mackie HUI, which has eight faders, were born. You can't perform the whole mix like you can if you have more faders. But on the other hand, you can't move all eight at once anyway, so in that sense you have more than you need.

Oh, and I assume you know about scrolling up and down in banks of eight faders (or one at a time)? That lets you control any channel in your DAW; the only limitation is that you get eight at a time. Sorry if you knew that already.

The "standard" way to send your synths to the DAW is to use the eight busses. Be aware that DA7 busses aren't like the busses in an analog board, because they're not hardwired - you can pretty much route any input to any output. So the concept of busses, etc. is all sort of a virtual paradigm.

Still, I have my Pro Tools system set up exactly like yours: busses go to PT, PT outs are connected digitally to inputs 17-24. Synths in 1-16.

I figured since you were running Pro-Tools it might have been a little different in config. Why would you use the busses out into pt? Wouldnt you just send each individual out instead of a bus (only eight???)?

"Tell me more about these buses" (in evil voice, tugging at my beard ) lol

I recently added an ADAT Bridge interface, so I have a potential 24 inputs into Pro Tools, but before this I only had (and needed) eight. You can use the direct outs if you have enough inputs into Nuendo, sure.

I've been using VIs these days more than hardware instuments. The "outboard" instruments I use these days are 99% GigaStudio, and then mostly orchestral sounds. That lends itself to submixing in four stereo pairs, i.e. strings, brass, ww, perc. - hence the eight inputs.