The Alaska highway is just a long paved road although there may be sections of construction; just as there may be on any long paved road. Having said this, it wont hurt to use a decent load leveling hitch. I would not hesitate to carry some weight in the back of the pick-up as well. In truth, a trailer that light should be no problem.
It doesn't hurt to stop along the way and check your bearings and brakes. Especially on a new trailer, bearings will loosen off in a couple thousand miles. Also, trailer manufacturers have a tendency to use just enough axle to be legal and bending of the axle is not uncommon. This is why you want your trailer to sit level, with equal weight on each axle, before you start travelling.
Every highway I have travelled is bad when pulling a trailer. It is, apparently, impossible to build an overpass or bridge without putting a ski jump at each end. If you add in the frost heaves and collapsing substrate on the rest of the road, it can be rough going. GD
