Basically i do not use archers anymore - before i have an access to technology my enemy runs around with lord hammers and 5-10 defence which makes bows useless, taking into account also that you have to build special buildings to produce them ... It is just better, actually must-be, to go after high attack melee weapons.

Battle Magic is also quite useless on ridiculous level - if stupid spiders you meet at the beginning of the game have 30-40 hp it requires 40 intelligence (11 level) of cast speller to cast two magic arrows to kill them .... With this high hp enemies you need i do not know how many channelers and huge mana income to base your military power on magic ..

Similarly, summons are useless too - i never used them

the only way to victory is strong army (one is enough - teleport spell is so cheap ...) By the way, i do not know if it is bug, but your sovvereign can cast teleport even if he has not enough of intelligence ...