Trailer Setup
I believe that one of the most important factors in towing a light trailer successfully are the electric brakes. When we first purchased ours we towed it home on the Interstate with out any issues. However since then we have had a couple of moments where the trailer swayed, not severly, even with the friction anti sway bar.
The solution to sway is not to try to correct the sway but rather to tap on the brake controller's trailer brake activation switch. This lightly applies the trailer brakes tugging it straight in a second. (Generally I find sway is created by potholes or bumps and wierdly shaped trucks like car carriers.)
In a typical three or four hour drive I probably activate the trailer brakes once or twice.
It appears that your trailer is about 200-300 pounds heavier than mine empty. Our axle is only rated for 2600 pounds versus your 3500 pound axle. I'm sure some of the extra weight is the axle.
We do carry a lot of stuff because of the nature of our travels. In the rear of the Honda we carry three metal chairs, a generator, compressor, bottle jack. To counter the additional weight in the rear of the Honda and the tongue weight of the trailer, we increase the rear tire pressure beyond normal, to about 38 pounds.
We carry about a half a tank of water, primarily for lunch stops, except when we're dry camping we then fill the tank. We hardly ever carry anything in our black and grey tanks except for a couple of gallons that we put in the black and grey tanks before we take off to slosh around while we're driving. We have also put ice cubes in with the water on occassion to help shake loose 'stuff'.
We also only have only one propane tank (full about 40 pounds a tank for the normal tank). We thought this might be a problem, the potential to run out of gas somewhere. The fear was needless. Gas lasts a long time if you're not running the furnance and when it gets low, feels like 25 lbs, I just have it filled. In a year of RVing I would guess we filled it 4-6 times.
I think trailer tires are important. We use Goodyear Marathons and keep them at 45 pounds, rated for 50 pounds max.
As to Tow vehicle brakes, I think it's rare that the tow vehicle can't handle stopping for normal every day stops, but not if you drive like some do, race up to a stop light and put on one's brakes. Without Trailer Brakes that trailer can do some awful things in emergency stops.
The real scarry times we've had have been in long twisty down hills in our motorhome. Brakes can heat up fast, no matter how big the brakes. We have learned to downshift on any long hill - we use the Mountain Directories to know where the hills are.
I agree with Steve, trailer brakes and a brake controller are a must.
I also agree that the first thing to do is to weigh the trailer and determine the hitch weight. The latter can be done with a bathroom scale. There is also a way to measure the trailer weight at home if a truck scale is not locally available; most truck stops have one.
Regardless of the tow vehicle I would get an antisway bar, the price is right and they are very easy to use, about as complex as the safety chains.
Though I don't own a weight distribution system and haven't personally felt the need on a small trailer. I do notice that most of the larger Sunlines have one.
Reese makes a weight mini distribution system for small trailers with hitch weights of 100-350 pounds, it costs less than $300. The following is a connection to this hitch
http://www.etrailer.com/p-66041.htm
In terms of priority the trailer brakes and tire pressure are first. weighing the rig and adding some kind of anti -sway device next.
Safe trailering,
Norm Milliard