Vis, in your desire to be closer to the crude primitivism of fantasy with unwashed peasants and torches, can you only remember the Garand rifle from World War II? Your MAGICAL SHIELD will help deflect a glancing blow from a sword, but it won't deflect a few grams of lead flying at several hundred meters per second. It's scary to imagine what kind of destruction a mortar or even just one artillery piece could cause in such a fragile world, far surpassing the latest and most advanced arquebuses and cannons of the red-skinned people. It's long overdue to understand that technology beats magic :)
Guys, I regularly have sword fights with these cool fantasy enthusiasts. They all wear stained leather jackets and t-shirts with Russian rock bands, with dirty, greasy hair hanging down like fat sausages.