I'm glad you went out and listened to subs at local shops in your area. It's a very good method of gaining knowledge and experience, getting an idea of costs, an understanding of sound quality performance differences between sub brands and sizes as well as determining what you like.
The truth is that a pair of good quality subs, properly positioned and configured, would provide very good bass performance in your office at a single designated listening position such as your desk chair behind your desk. You could also save some money by buying a pair of good quality subs online with a free 30-day in-office trial period.
The main advantages of using the Audio Kinesis DEBRA 4-sub DBA system are that the bass will not only be even faster, smoother, more detailed, more powerful, more effortless, with better dynamics and more natural sounding overall than a pair of good subs but it will also sound like this throughout your entire office, not just at your desk chair.
Duke has often stated something like: "2 subs will sound twice as good as 1 sub, 4 subs will sound twice as good as 2 and 8 subs will sound like good grounds for divorce to a lawyer." The 4-sub DEBRA does cost more than many pairs of subs would at $2,800 and requires a bit of a leap of faith to even try but it'll perform better and the risk is mitigated by James and Duke offering a free in-home trial period.
Of course, it's completely your decision whether you're satisfied with very good bass response at your desk for a reasonable price with a pair of good quality subs or you're willing to spend a few hundred dollars more and achieve exceptionally good bass response throughout your entire room by using the 4-sub DEBRA. I'm fairly certain both options would provide bass that blends very well with your main speakers.
Most of your questions/concerns you posted about wiring and cables are addressed on the thread I started awhile ago on the DEBRA system linked below.
https://forum.audiogon.com/discussions/anyone-else-using-an-audio-kinesis-swarm-or-debra-distributed...
The DEBRA's supplied sub amp/control unit has dual speaker output terminals, labelled as A and B, and this thread details how the final sub cabling hookups are done in a series/parallel method:
Attach a single wire from the amp’s speaker A’s pos. output terminal to Sub#1’s pos. input terminal.
Attach a single wire from the amp’s speaker A’s neg. output terminal to Sub#2’s neg. input terminal.
Attach a single wire from Sub#1’s neg. input terminal to Sub#2’s pos. input terminal.
Attach Sub 3 & 4 using this series/parallel method on the amp’s speaker B’s output terminals.
I planned out all the wire lengths (with a small margin of error inches added to each) and ordered single, high quality and low gauge speaker wire along with the sub system for a very reasonable price from AK's James Romeyn in Utah. Once the ideal locations for the subs was determined, I drilled holes in my room’s carpeting and subflooring to the crawl space below, and was able to hide all of the connecting wires.
Each sub comes with a set of 3 brass spiked footers for positioning on carpeted floors. These raise each sub about a half inch off the floor which allows the clearance for the running of speaker wires to each sub's input terminals located on their bottoms.
If you don't have a crawl space or basement located below your office to run and hide the wires, there are other options for doing so such as running them behind baseboards, inside the walls or through a drop down ceiling or an attic. Another idea is to run the wires in a plastic conduit that could be attached to the top of your baseboards in a matching color so that it appears to be a part of the baseboards. You could probably do it yourself but it may be easier and less frustrating just to hire an electrician to do it. I'd suggest avoiding running them underneath wall to wall carpeting mainly because it seems too permanent to me and you may have future ease of access issues to the wiring.
Later,
Tim