A few thoughts…

If you don't want a toy hauler then you're not really going to have much space to carry 3 bikes inside. I won't say it can't be done but you'll have to carefully fit them in after pulling the slides in and will have to worry about grease getting on things or scratching woodwork.

If you're going over 40 feet…check the actual loaded gross and pin weights of the trailer…with a 350 you're going to be very close to exceeding weight limits, particularly the rear axle limit which is almost always the first one you reach.

If you don't get a sat dish on the roof you won't have a lot of TV in many places…the number of channels available over the air continues to go down. You can get an outside antenna…but then you've got to store it and if you want HD capability then the portable units are pretty large and also somewhat hard to aim so you may not feel like putting it up for say  a 2 night stop.

Any toy hauler that's less than about 42 feet is really going to have somewhat cramped living space…which could be a problem both from the "enough space for 2 people" standpoint and the "there's less cabinet space because there's less wall space to put them on" standpoint. And if you're in the 42 or more length then pulling with the 350 is going to be even more iffy.

You need to get the appropriate towing guide for your particular make/model/year of truck and see what the limits are. Add in fuel, hitch, passengers, tools and the real weight of the trailer and pin…not the number the maker gives you which is empty and doesn't include any equipment installed later like awnings which are frequently installed by the dealer…don't forget to add in water, food, clothes, bike parts and everything else. This obviously varies…but in our case our 40 foot New Horizons is 18,420 dry and our recently obtained as towing weight is 23,320 for the trailer…this was with empty black and gray and 30 or so gallons of fresh…so the cargo is about 5,000 pounds. Also need. to take whether you have an aux fuel tank in the bed into account when doing the weighing. There are easily available spreadsheets on the web (or I have one that I got from Bill Napier) to help do the weight calculations. While obviously you need to do the real calculations using your truck and rig…my guess is that if you try to pull a 40 footer with a 350 you'll be over the rear axle at least. Will it start and stop? Sure. Will it stop quickly enough in a panic stop to both prevent hitting something and maintaining control? Maybe not. Is it really safe? Maybe not.

I would stay away from the front LR models that have the LR up over the kingpin and the BR in the rear. There's less ceiling height up in the front naturally…and you are better served having the tall ceilings in the room you'll spend more of your life in.

I just carry my bike on a rack on the rear of the rig…got a pretty decent waterproof cover from Amazon for 60 bucks or so. They only last a year or so before the zippers give out from all the sun and road grit on them so I just figure the cover is an every two travel seasons replaceable item.

I'm an old retired submariner myself…two tours on fast attacks sandwiched around one at Auburn University NROTC…then spent the rest of my career in the acquisition business buying first torpedoes and then secret stuff for Uncle Sam's Canoe Club.