Africa being what it is, I would keep my options open in the event of an unfortunate situation; IOW, there might come a time when having non-removable, BRIGHT items on your pack would be undesirable. Throw some black pouches on the thing, like an admin pouch, and possibly some water bottle/water filter pouches on the side.
The Condor TNT pouch is great for holding small stuff ready for easy access:
http://www.combatsportsupply.com/condoroutdoortandtpouch.aspx. This pouch is
really nice for organizing the small, and frequently used items that one carries. Hard to see, but there are two small Velcro tabs on the sides that (1) provide zipper back-up, and (2) will provide an audible warning should someone decide to "lift" things from your TnT pouch. The same vendor offers pouches that could attach to the sides of your pack.
You could kill two birds with one stone by buying two side-mounted TnT pouches:
http://www.combatsportsupply.com/condoroutdoorsidekickpouch.aspx. While not quite as versatile as the larger, flat TnT pouch linked above, they don't add any depth to your Pack, either, and two of them should fill the needs of all but the most dedicated pack-rat.
I trust Condor in inverse ratio to the weight being carried. These pouches, by design, are for small, light items, and mine have held up well. I have yet to find a better designed pouch of its' type, and I've looked far and wide.
If you do not have the optional frame sheet that Spec-Ops offers for your pack, I
strongly urge your to get one. It will transform your pack.
The "Vent Panel" seems interesting for high-heat situations.
Both items, and a lot of other useful accessories designed for YOUR pack here:
http://www.specopsbrand.com/packs-bags/pack-accessories.html.
Another idea is to take some Velcro OneWrap, and weave it into the existing PALS webbing. Done right, any sort of patches or logos could be attached there, and the whole rig could be removed or re-configured as you wish.
Disclaimer: no financial interest.
These packs are all over the place, and I don't think that most of them will get a second glance. Your bearing and appearance will have more to do with your being noticed--or targeted, if you wish-- than what you are toting.