Keep Level 10
Arsenal Level 30
Tavern Level 10
Library Level 10
Fortifications Level 20
Market Level 8
Farm Level 30
Lumberjack Level 30
Wood Store Level 20
Quarry Level 30
Stone Store Level 20
Ore mine Level 30
Ore Store Level 20
A maxed out farm allows 5000 subjects. With a maxed out castle the buildings and researches make up 935 subjects. That leaves you with
4065 subjects.
Balanced castle
600 spear
600 sword
600 archer
600 crossbow
400 arm horse
400 lancer horse
Offensive castle
400 spear
800 sword
800 archer
400 crossbow
200 arm horse
600 lancer
Defensive castle
800 spear
400 sword
400 archer
800 crossbow
600 arm horse
200 lancer
You can play around with your preference but I recommend your first castle be balanced.
There are offensive and defensive troops. Only use offensive troops to defend when you absolutely have to.
Offense troops
Swordsman
Archer
Lancer Horse
Defense Troops
Spear
Crossbow
Armored Horse
Never use defensive troops to attack