Here are my 2 cents,
Im also Portuguese and i read alot about our famous medieval battles vs the spanish and from what i read i've come to this conclusions,
The Portuguese army was a drafted army mostly BUT our peasents were all armoured and had their own weapons and armour most of them and as they were fighting for independence their morale was always skyhigh.
we mostly relied on lots of heavy and light infantry, few knights, few light cavalry, a lot of tricks and traps and very good genrals, our forces remind me of scotish forces to some point.
The Spanish were a more professional army as they already had a kingdom and they were like a french army but as they were more professinal army they had a lot more heavy cavalry and more infantry in numbers not quality and lower morale as they were fighting for cash not their country.
Our battles were mostly us defending very outnumbered but vs a eager but not so smart enemy as they always though we were easy pickings. much like france vs english at agincourt, instead of longbows we used pikes and heavy inf, + oil traps
I think the game could be much more improved in our armies and its 2 easy 2 conquer the spanish with Portugal in the game, in reality it wasn't so easy fighting them
Cya