Good point on the size of the box - I know the midsize trucks use the "can you fit a sheet of plywood" metric and the answer is "yes" but over the wheel wells (wheras 1/2 ton and larger can fit the sheets between the wheel wells). Of course, that means much greater width on the 1/2 tons, which limits some off-road and remote area capability, so everything is a compromise one way or the other.
I'm also seriously wondering how this will be delivered -- there's something about a "chicken tax" in the USA that makes trucks made internationally difficult to import (I don't know the details) but I've read that a way around this is to import a vehicle that isn't fully assembled (i.e. chassis-cab configurations, with the bed added at the destination). If that's the case, I would LOVE to see a partnership with a company like Norweld or Mits Alloy to provide a factory tray-and-canopy option. In your use case, Mountain guy, the tray would be perfect for moving around an ATV and lumber while preserving the width of the truck for remote area access, so being able to spec it that way from factory would be fantastic. You could always go with a "box top" deck - quite common for snowmobilers and such -- but they put the weight really high and I'm personally not a fan.
The other concern that I've been thinking about is the position of the rear axle. It's so far forward that it creates a significant load area behind the axle -- 2/3rds of the box appears behind the rear axle's centre -- which acts as a lever and inhibits carry capacity a bit and may post a challenge for campers and such. There are a plethora of broken-backed trucks out there because of this leverage, which gets particularly bad when off-road towing.
I can see the comparisons to the Gladiator as the shapes certainly do rhyme but I give the nod to Ineos on their design; one of the things I don't like about the gladiator is that it appears to be designed to look aggressive for the sake of aggressive rather than for any particular function. On the Wrangler, a lot of the design is practical for rock crawling, but the Gladiator uses the same design cues even though it's not super suitable for that purpose in the same way. The Gren Pickup seems to soften that aggressiveness a bit so I prefer the looks. I can see a fella using a Gren to go bird watching in tweed while he's not attending to his farm and looking quite at home in this pickup -- more like a country estate truck; the Gladiator has a vibe that's a bit more more "sun glassess, beards, and tattoos" (and as a guy with all those things, I'd probably match the gladiator better, but this analogy is an attempt to articulate what feels 'softer' about the design of the Gren pickup to me).
