All Amarrian technology is built to test the user's faith. Your suit? It's welded to your skin. Also, your suit is mechanically wired to your neural systems, which is INSANELY painful to the user. Amarrian Heavy suits use a special fabric that spread the heat of a bullet over a wider area, as to minimize actual damage. Of course, it still hurts the user more. Uplinks can legitimately cause cancer and other radiation-type diseases. The Laser Rifle originally had a fail-safe that, when it reached a certain level of heat, it automatically shut itself off until cooled down. The Amarr Empire altered the weapon so it just hurt the user instead.

TL;DR, not only is overheating and feedback damage a balancing factor, it's also fitting with how Amarrian technology works. To test the will and faith of the user. Because remember, even while going through so much pain, you can still run the furthest before giving up.

It says, the Amarrian Medium Suit is grafted to the user, and the suit is linked to the neural systems of said user, causing a bunch of pain.

Caldari Assault

The Caldari dropsuit design and aesthetic philosophy is heavily influenced by the cultureGÇÖs origins on brutally frigid home worlds, dismissing stylistic notions in exchange for the ruthless, bare-minimum functionality requirements needed to keep a soldier alive. As such, the Caldari suit is notoriously uncomfortable and outright ungainly in some instances, yet remains in high demand due to its remarkable resilience in smart battlefields.