The problem with smithing is tha with medium levels smithing 50- you don't get almost any profit, as for exmaple, you need 48 level of smithing to make a steel platebody, although you only need 5 levels of defense! They could increase the stats needed for wearing armor (and thus the protection that they give) like:
Armor Actual def lvl New def lvl
Bronze 1 1
Iron 1 10
Steel 5 20
Black 10 30
Mithril 20 40
Addy 30 50
Rune 40 60
Dragon 60 85
That would give smithers a bigger profit to make, and would encourage people to mine in order to smith. Also, in real life steel only needs like a 10% of coal for the iron (correct me if I'm wrong) so, instead of having to smelt 2 iron ore and 4 coal (600 gp only for the coal) to smith a steel scimitar only useful too people with 5-10 attack, it could be like:
Armor Actual ores needed New ores needed
Steel 1 iron, 2 coal 1 iron, 1 coal
Mithril 1 mith, 4 coal 1 mith, 2 coal
Addy 1 addy, 6 coal 1 addy, 4 coal
Rune 1 runite, 8 coal 1 runite, 5 coal
That would bring less profit to miners, but more to smithers. What do you think?