There is probably a better way to do this but I like to keep things simple for my brain during creative process.
So my thinking works like this:
- I record all of my instruments on separate tracks in Reason 6.5
- Everything that I play (and then record) gets routed into the Scarlett 18i20 (and Behringer ADA8200)
- Maschine is one of my ‘external instruments’ - I think of it as though it was running on a separate computer, use it mostly from the Maschine I hardware and in my head it is an instrument (very full-featured) just like all of my hardware instruments
- ergo, it runs out of a separate audio interface (AK-1) and gets routed on balanced inputs INTO the Scarlett
I think of this setup like a ‘looping paradise’. Instead of trying to escape the creative trap of just jamming out on a single loop - I have embraced it. On hardware I can have 34 differing loops/tracks at once that can all be realtime tweaked, muted etc…and if I want more/different, I can add unlimited with the Maschine 2 software…and more inside Reason itself if I want to. So I can create all these bits and pieces that work with each other, riff out on a single loop for hours and then when I have lots of bits that can be tweaked etc in realtime, hit record and lay down to 6 stereo + 1 mono track in Reason.
This setup gives me the ability to apply Reason effects (which I love) on any of those tracks while jamming, or post.
Before this I was recording to stereo - using a similar concept but everything was routed to the OT and then tracked in stereo to Reason. All that left me to do was chop out repetitive sections (where I hadn’t done much tweaking at that point) and do some mix/master treatment of the stereo track. Now I can chop up the parts and do some arrangement/construction with them after recording (yet to give this a really good workout but it works in my head).
Now, if I wanted to fork out cash for another DAW and get away from Reason, I could of course route more separate Maschine tracks (I do have the option to export those as audio if needs be) and I could do this using the Maschine VSTi instead of standalone. And having tried this once or twice with Ableton Live Lite and Reaper trial, I know I can wrap my head around it. But I just love the modular nature of Reason, that tab button and the routing options are still unsurpassed IMHO. I love the Reason mixer almost as much as my Easel and I love the look and feel of Reason, with all this hardware around me, it feels ‘right’ to use the old-fashioned rack concept of Reason.
I think Logic is about the only DAW I haven’t tried at some point…but that’s 200 bills and probably some learning curve.
I looked at many many mixers for a very long time - none had enough stereo inputs (I have a Soundcraft Compact 10 which has 6, most I could find and that’s what I used before upgrading to the Scarlett w/ Reason as my main mixer) and they all take up too much space. This way I got all the I/O and routing I wanted and it only needed two racks worth of space - fits easily on a shelf tucked out of the way. I have enough instruments to tweak without feeling like I need the hands-on aspect of a physical mixer.
I hope this lengthy post answers the question 
If there is a neater/better/cleaner or just alternative way to do this routing or anything you think I should try I am very keen to hear it.
After months and months and months of thinking, drawing routings etc. I finally feel like I have all of my audio and all of my MIDI going pretty seamlessly where I want it to go as soon as I fire everything up…and almost no gearlust (even AR isn’t really tempting because it is so damn expensive) now to spend some more time jamming with all these fun toys and lay down some more recordings - I love jogging to my own tunes (ok, to one or two tunes I recorded that I play on repeat a lot…)