The DT is for loads and the tubing spec makes it clear when riding it unloaded, the Atlantis too. I'm not quite as confident about the Appaloosa relative to loaded touring versus loaded shopping compared to the Atlantis. The website has Grant's Appa pictured and described as an everyday bike.
The DT's long top tube is expected from a loaded touring bike and its intentionally longer wheelbase and chainstays. It's a bit too long for me, even with a short stem. I could have picked an even shorter one but it begins to destabilize the front since it wasn't made for that like Analog's bikes. I could have picked the next size down for a closer top tube fit but I'd have to shop for super long setback seatposts, the rare high rise threadless stem and a Shriner's fez. Riv addresses their longer top tube recommending upright swept back bars.
Rivendell pins the Atlantis as their identity bike. I feel like it's road sibling, my Rambouillet, should have had equal billing but lost out in their unifying definition of bikes being more utilitarian, which I get. Bikes should also be fun and the Rambouillet is that. The road models, Roadini and Roadeo, are now less utilitarian than the combo/Country bikes, Homer and Sam or my Ram. In the Sam and Homer descriptions they even say to look at the Appaloosa if loads above 35-40# are going to be your gig (not the Atlantis?).
The few times that I've taken my Disc Trucker on rides beyond ten miles for its dyno lighting I found it uncomfortable and unnecessarily beaten up because of both the too long of front center and the too rigid ride compared to my Ram. I shared these perceptions when having a frame and fork made for me by Johnny Coast so he could pick tubes to reach the balance of being able to carry a front load of 20-25 lbs but not ride like a truck the rest of the time when ridden unburdened. Besides being designed to my dimensions, it is a very comfortable bike and has accommodated all of my riding very well. If I were of stock dimensions maybe the DT would be a good ongoing chassis keeping me from seeking better. I suspect that even if of a better fit that I'd find it too sturdy to reward my appreciation of more lively framed and forked bikes.
Do you load your DT for much of its riding? Do you use it as an every day bike with occasional service as a beast of burden? Do you take it out on long rides for your enjoyment? Do you ride it on trails? These would be good guides to decide if the Disc Trucker has been the optimum bike for your uses. For me it was less than optimum in fit and heft of construction but cost less complete than anything more bespoke and was of a stable geometry that suited my needs.
Andy Cheatham
Pittsburgh