If it were me, I’d be looking at a 7’X12’ V-nose. They’re comparable money to a 6’ wide, but, gain a lot of extra floor space and allow plenty of room to get around the bike. If you should add another bike (like you and your buddy want to go to Sturgis, Daytona, etc), you can easily stagger them and still have plenty of room to move around the bikes. If you should move into a Can Am Spyder, you’ll have plenty of room for that. You can easily haul up to a 60” lawn mower. You can add shelves and cabinetry, in the nose, for more storage and take some of the rarely used items and weight off your coach. I just think it’s a lot more versatile size than going with the minimum you can get by with.
I’d do a 7’ ceiling height. I can tell you, it’s very unpleasant to hit your head on the top of a door opening. Also, the extra height allows a “barn door” windshield to easily clear.
Be sure and get a torsion axle. It’ll make a huge difference in ride for your cargo, as well as jerkiness and vibration you feel inside the coach. I’d option a 5K or 6K capacity axle. The standard 3500# axles most come with just aren’t enough. If your empty trailer ends up at 1700lbs, that leaves 1800 lbs available for cargo. That’s 2 touring bikes. Some may say to just get a tandem axle trailer, but, they’ll eat tires and get worse fuel mileage than a single axle.
You mentioned trailer brakes. I’ve had with and without. I will never again purchase a trailer without them. They make a huge difference, especially when someone pulls out in front of you or you’re up in the mountains. I’m big on the idea: If there are tires on the ground, they need to have brakes.
Lastly, I’ve owned and pulled a variety of box trailers (10’-24’) and have ~40K miles on my current one. I’ve never pulled a nicer made, nicer riding trailer than a Featherlite. There is a definite difference in how trailers are made. In turn, that affects their ride, longevity, resale, etc.
2018 Thor Four Winds 24F