Sorry if this double posts, but my first one seemed to disappear....
The most constructive advice I can give is that the configuration being attempted by the OP has the potential to frustrate even the most technically savvy Windows audio hobbyist or professional. Using 5 different audio devices of different manufacturers, different drivers, and all as simultaneous inputs to a Windows DAW is the stuff of troubleshooting nightmares, no matter how determined you are. You will get very close (as it looks like you have), and something else will happen to undermine your confidence (like scrambling the inputs). Unless you get extremely lucky, you could end up chasing stability or performance that you can never achieve. I've been there, even if just because I like to push my hardware and knowledge to the limits to see what it can do. Let me explain (at least from my experience).
Windows DAW software has not had a good history of being able to "combine" audio devices without compromises. I heard iOS can integrate multiple audio devices better, but I have never been a Mac user, so I can't comment.
Choosing ASIO4ALL to attempt this is probably the best thing to try if you are trying to achieve ASIO level performance. For all its good and bad press, ASIO4ALL is an amazing piece of free software, especially when you get lucky and it works in your configuration. I've seen ASIO4ALL do things that the native ASIO drivers could not do, and I still can't explain it. BUT, even when it "worked", there were always gremlins. Many of ASIO4ALL settings (expert mode) are mysterious, unpredictable, and likely would need to be tweaked PER audio device to get them all synced and stable. That is a LARGE number of variables to tackle for 5 different inputs. And then you go down the rabbit hole of endless tweaking and never quite getting the same performance or the stability of one rock solid factory driver. For this reason, many warn to stay away from ASIO4ALL, even though it DOES work very well in certain situations.
Another alternative (for SONAR anyway) is to attempt to use the non-ASIO (Windows driver) models if they are available for all your inputs. SONAR audio configuration allows you to select multiple (non ASIO) audio devices for simultaneous use. The "gotcha" however is that those drivers (especially in combination with one another) rarely achieve the level of performance of ASIO drivers. If you are very sensitive to latency (delays) for virtual instruments or live monitoring, then you may not be happy this this approach, either. In my tests, I was never comfortable with the non-ASIO performance for my needs. However, if you don't use virtual instruments and don't monitor your inputs through SONAR, this might work for you.
Now to the last point.... even IF you get 5 different audio devices playing nicely with one another, the original problem of SONAR (or other software) scrambling the inputs (and/or outputs) of multiple pieces of hardware is also a fairly common complaint that I've experienced myself with "off normal" configurations. The behavior you describe when the precise order of powering devices, or the unpredictable driver order of devices powered on simultaneously, or the accidental "leaving one device off" when starting SONAR, or any other variation on the theme, seems to cause SONAR and other programs to "intelligently" reassign inputs and outputs based on what it thinks you DO have at the moment. I have never found a way to force SONAR to lock down input and output assignments when it thinks the hardware configuration has changed. This scrambling of input/output order has affected MIDI devices for me also.
I'll wrap this up. I responded because I've probably spend hundreds of hours myself trying to make audio/DAW software do things that are on the fringe of "normal/stable" configurations... and I always lose. I get SOOOO close. In the end, I purchased different modern hardware with supported drivers and enough inputs, and my troubleshooting nightmares (or at least my wasted time) went away.
I wish you the best in making this work.. and maybe trying SONAR's non-ASIO drivers is something else you can try, but I am just cautioning that trying to get 5 different audio input devices working well/simultaneously on Windows might make you crazy and more obsessed with fighting computer/DAW settings than making music.
This is a big reason why many advise to choose ONE brand of well respected hardware with enough inputs to cover their needs. It's probably not what you want to hear, but you'll have fewer nightmares. I know I did.
Good luck