Hey Rob, not the most helpful reply I realize, but I'd try asking the Frost River folks directly via e-mail, phone, etc. as they seem to have been around for awhile, and seem to have a good reputation per what I've read in other forums (e.g. bushcraftusa). I'm sure they'll reply with honesty and be upfront about any limitation.
As for me, when I was in the market for different packs (day pack, backpacking pack, bushcraft use pack) during the past couple of years, I came to a conclusion that it's nearly impossible (though I haven't given up hope yet) to find a pack with the combination of modern suspension with old world looks and simplicity. I love the freedom that an old style pack provides in terms of how one can pack the main compartment, and the protruded outer pockets for frequently used items. Whereas the modern backpacks (whether they may be tactical or geared towards backpackers), though I love how comfortable and light current suspensions are, don't have the look of the old, nor do they offer comparable methods of storage (everything is either zippered sleeves inside, or sleeves on the outside with no flaps (and also the tactical packs have additional storage units with molle type attachment methods, which I just don't like the look of).
Currently, I use:
1. Granite Gear Blaze AC 60 for backpacking. Of all the semi ultralight backpacks, I found this one to have the best suspension (adjustable, nice fat and cushy waist belt, and simple and intuitive compression straps).
2. Gregory Miwok 18 for daypack. Superlight, and molds to your body very well. I love that the waist belt has a zippered pocket on each side. In this bag, I typically carry a 32oz SS bottle with cup, Sawyer Squeeze filter, original space blanket, Maxpedition EDC pocket with some basic surival tools, a hatchet, first aid kit, headlamp, bug spray, compass, and a rain jacket (and sometimes a collapsible trekking poles as sometimes I have knee issues). And I can carry a GPS and my cell phone one each of the aforementioned waist belt pockets.
3. Granite Tactical Gear (tactical line from Granite Gear) Special Mission Assault Pack - Again comes with an awesome suspension and relatively light for a tactical pack with almost 40L capacity. I can fit everything from my day pack AND a roll of twin sized wool blanket, and then some. Only downside with this bag is it lacks compression straps and it's almost becoming a deal breaker for me. Have talked to Granite Gear folks and they can integrate a compression strap for me custom at a moderate cost (~60 USD).
I may go for that or continue searching for a better bushcraft pack (for my use and personal liking), but since most of my bushcraft outings are single day variety, my day pack does the trick very well (and I know I can last several days with it if I ever got into that situation). And it looks like any other modern day pack, so it doesn't bring any unwanted attention from those who find bushcraft type of people weird.