Frame options for chromoly steel, preferably cargo bike?

I've had a custom built bike using an ebikes.ca kit for many years, but looking to upgrade as my current frame has a number of issues and want one of the newer V3 all-axle motors. I don't want a prebuilt bike, in fact I'm fine doing everything myself besides the frame as long as it's mostly standard part types and will be re-using most of my electronic parts, I'm just out of touch with what the options are these days for frames. I'm looking for: * Chromoly steel * A more cargo oriented frame, though I suppose I could look at trailers too? * Disc brake support (kind of a given now I guess) * Ability to mount fenders if possible * Preferably something that allows larger tires, as I bike in winter where it snows, plus it's smoother and suspension doesn't make any sense for my setup I know Surly makes solid chromoly steel frames, but their cargo frame "Big Dummy" doesn't appear to allow anything larger than 2" on the tires which is almost smaller than what I have now.