A monopod can greatly expand the situations where you can get your shot, decrease your strain (if your camera is heavy you are no longer holding it up; it rests on the tripod when shooting or when resting), and usually don't trigger the same scrutiny as tripods.
A small tech cam can give you fantastic quality in a very compact package. However, it's a very different kind of shooting and I'm not sure I'd recommend such a switch right before a big trip (better to have time to practice and get used to the new system). The
Cambo RC400 and
Arca Swiss Factum are good alternatives to the TC/STC.
But back up for a second. The first step in planning anything is to define your goals. When packing for a trip I first ask myself this essential question: "is it ok (for this trip) if there is a shot I can't get?". When the trip is professional in nature the answer is often no, in which case I'll pack more zooms, more lenses total, bigger flashes, and more than one body (backup and the ability to have two lenses ready instantly). If the trip is personal the answer is often yes, in which case I pack less lenses (only my favorite primes), only one body, and a small flash (if any). Sometimes on such a trip a potential image comes up that I can't reach with my lens/body/flash combo, but it does not bother me.
I find often that too many options are beyond my photographic ability to take advantage of. In other words if you put me in a situation with a single prime lens I will often come out with better images than if you give me three primes and an ultrazoom. There are very likely much more talented photographers out there who can pre-visualize compositions in multiple focal lengths simultaneously; but I can barely think through compositions in a single focal length.
From this point of view I think I would suggest either your M9 OR your Monochrome. Since you bought the Monochrome that implies you enjoy the idea of being limited to one kind of rendition (B+W). So embrace that! If you're bringing your medium format kit think about what situations it will excel in over your Monochrome and stick with the lenses/bodies/accessories for those situations. Having "full coverage" to me is vastly over rated for personal shooting.
On one personal trip I took an
infrared digital back on a tech camera with a single lens... to shoot a football game. There were any number of shots I could not get, but I just let them fly by me without concern; the images I did get are very meaningful to me.