Using old FRP pics as a reference for the current fluff is like using the Rogue Trader book to get the look of your Space Marine army, there\'s no reason you can\'t but stuff has moved on. The imagery of the Warhammer world has diversified and developed since those days. All of those pictures (with the possible exception of the last) could be illustrations from any history book dealing with late medieval warfare.
All the Warhammer races now have become stylised stereotypes of their equivalent cultures in real history. The Empire corresponds to the Holy Roman Empire only with a darker, more superstitious and morbid feel. Brettonia has become very traditional Arthurian legend based with a healthy hepling of Monty Pythons Holy Grail thrown in.
The current depiction of Estalians is basically Don Quixote meets new world conquistador. Everyone has a comb morrion helmet and a thin waxed moustache and goatee. The best stuff to get hold of really are Pizzaros lost legion or the old morrion wearing Empire swordsmen and handgunners.
The Occidentals from the
Hell Dorado game are probably a better place to draw inspiration from. Failing that play Medieval Total War as the Spanish lol