All imperial age blacksmith upgrades ranked

The blacksmith upgrades are an integral component of a strong military. They are relatively cheap and mean the difference between winning and losing skirmishes. But which ones are the most important ones? Obviously it depends on the units you make, but in general it is something like this, from most to least important:

1. Bracer - This is a no brainer. Bracer increases both attack and range, which is crucial for archers. It also benefits towers and castles too.
2. Blast Furnace - It is debatable whether +2 attack or +1/+2 armor is more important for melee units. I prefer +2 attack when against melee units and +1/+2 armor against ranged units. However, Blast Furnace benefits both infantry and cavalry which tips the scales in its favor.
3. Plate Barding Armor - Armor is very important for cavalry. It makes them take a lot more arrows to fell and lets them fight in melee better. Since cavalry is more useful than infantry overall, I prefer this over infantry armor.
4. Plate Mail Armor - As with cavalry, infantry benefit trememdously from armor. Surviving more arrow fire and slashes is always a good thing.
5. Ring Archer Armor - Archer armor is more situational than the other blacksmith upgrades. You often place ranged units behind a meatshield, or kite with them. While it is useful in certain situations, notably archer vs archer battles, this is without a doubt the least important blacksmith upgrade.

Which blacksmith upgrades would you get first?