Welcome Qira123!
-Your tow rig, is an easy match for your trailer, I'd say even loaded. Mine is a 7x16 Tandem Cargo Craft, was 2,200 dry, now 3,000Lbs loaded with gear. Tow rig was '95 Ford E-150 5.8L/3.55 (nowhere near the power/torque and cargo capacity of your 2017 Silverado), pulled it fine. Now the tow rig is my '02 Mitsubishi Montero (Full Size), 3.5L V6/4.30 gears, 5 speed auto. Again, no problems here either, as a matter of fact, I prefer towing mine with the Montero, due to gearing and AWD options. I would just put a check mark as "good" by your tow rig for the trailer you are considering, and move on to other questions.
-Extended tongue. What for? The other poster mentioned a Jeep wrangler, with spare tire mount. Your truck only has the tailgate to clear. Your existing spare tongue space is taken up by the V. Do you need the space inside or outside the trailer? If you want the V for fuel efficiency, might as well mark that off the list too, reportedly, it really doesn't help. I chose the standard flat front to provide a "squared" interior to build off of, and traditional space on the tongue for a box later.
-I'm running a 6,500 btu window A/C in the Southeast U.S. with 1" styrofoam insulation, and a bit of fiberglass in the ceiling curve, and it does the job nicely. I imagine a 13,500 in a insulated trailer in your area could create a meat storage locker. (ha!).
-I too chose standard straight axle, no 4" drop, to gain ground clearance for the forest service roads, and steep road entry/exit to hilly areas. I just use slightly longer ramps to load the lawn mowers, and sometimes crank the nose jack to change the angle if needed. (barn doors in my case).
-For planning, always get a trailer, 2' longer than you think you'll need. (I started plans with a 7x14, so glad I followed advice here).
-Yes to factory windows, high and offset for crossflow, light, and interior wall space left. (thanks to forum member gonefishin)
-Stab jacks at 4 corners, welded from factory
-36" RV door from factory, =best money spent.
-Plan on a multi-speed reversible roof vent, perfect for your area, and hunting destination.
-Having a single step at the RV door from the factory is nice too.
-Checkout vertical E-track, in my build, handiest setup I've ever used.
Here's mine, take out the kayaks, insert the ATV, add sink/toilet whatever and you're done.
http://www.tnttt.com/viewtopic.php?f=42&t=48345Not sure about your budget, but since you are close, go up and take a factory tour of Intech trailers in Nappanee. (Sister company is IntechRV). They build industrial, motorsports, custom trailers, all aluminum. Most of their stuff is commercial/government, but they do custom work, and for example, you might custom order one of these 7x14 fiber optic trailers, built to suit your needs, get a quality trailer and a deal in the process?
http://www.intechtrailers.com/fiber-essentials.phpAnother one close-by is Aluminum Trailer Corporation, check out the Raven line of Cargo trailers. Aluminum framed, probably not cheap, but since you will be traveling snowy roads sometimes...
http://www.aluminumtrailer.com/raven-cargo-trailerWelcome to the madness!