Best place ( blacksmith to upgrade archer)?

[Akumie]

Help

[Cuddle_Rat]

If you mean the bow I would say Bahtal or dwarven, armor I would recommend Vermundian

[Nekra]

Dwarven if you can, the knock down is super nice. I do dwarven for armour too as it allows you to recover from knockdown and stuns much quicker.

[Knavenformed]

Vermundian/Elven if you work with split damage weapons
Dwarven for everything else, including armor

Battahl is not worth the encumberance increase imo