Back in the 'old days' of recording the choices tended to be pretty simple, the choice of signal path was pretty much limited to the mics, one console & tape machine at hand - that was what you had to work with. So in that scenario you'd throw a mic on the source, get your levels, maybe a bit of eq, hit 'record' on the tape machine and move on....and then more or less the same in reverse for mixing (eg tape machine->console) ......obviously this is a simplification..
A drawback in these modern DAW times is an overwhelming amount of choices & possibilities, leading to cognitive overload & 'shutdown' of the mind !
I would therefore suggest to try and simplify things & have some main standard / default 'go to' items in your virtual nebula 'signal path' that you know well in terms of the results / sound / how to work with and that make sense for what you are looking for sonically..
Mixing IMO is a task that requires all senses to be focused on what's going on & things that distract from this by diverting cognitive resources should be avoided (eg: trying endless combinations, scrolling through 100's of plugins etc) ..
In the old analog days of mixing from multitrack tape, the signal path would go something like this:
tape machine -> (possible routing to outboard eq/compressor etc) -> desk channel -> (insert via patchbay - outboard eq/compressor etc ..or eq / compressor / gate built in the channel itself / fx sends) -> Subgroups (fx sends / possible eq/compression patched in)-> Mix/master buss out -> (possible eq / buss compression patched in)-> 2 track recorder
So it sounds to me like you are wanting to experiment with trying a 'virtual analogue' kind of path before you go and mix elsewhere.. so in that case I would suggest for your nebula preset bounce chain:
HO Tape -> MFC console line or mic channel (whichever sounds best..line makes more 'sense' though)
If there was a particular instrument you perhaps wanted to try using a mic pre to give the character of it having been recorded that way then I would suggest
Whatever mic pre -> HO Tape -> MFC console
Hope this helps!
(And, maybe you find a way that works better for your needs / the kind of sound you like!)