I've suggested pretty much exactly this on more than one occasion over the years, minus the ore part.
In my opinion, any commodity that's even remotely valuable, that is Cigars, Guns, anything with luxury in its name, drugs, diamonds, gold.....all that stuff should have much higher base costs - 5 000 per unit at least - and slightly higher profit rates as well.
Stuff that can stay as it is is food rations, consumer goods, fertilizers, that kind of thing, so that low risk routes are available as well - with somewhat lower profit rates.
The ore idea is interesting, but keep in mind that the "base value" of ore is measured in the time and teamwork it takes to fill a transport. I think that's fine as it is (and very few traders with a full load of ore will go "jsut kill me").