I like the idea of making power armor more complex (though this should not be limited to just power armor; segmented suits, different amounts of health for different elements etc.), however, I disagree on bonus functions.
A lot of what you wrote about additional subsystems (thermal imaging etc.) does not fit with the technology in Fallout. Fallout is retrofuturistic, inspired primarily by the way the 50s saw the future. The design of the technology is clunky, rugged, but reliable. Note the T-51b, the apex of power armour technology before the war. It is basically a plate steel helmet. Extra subsystems are limited to a polarized, bulletproof visor, a drop-down night vision eyepiece and NBC-sealed rebreather. This is because the technology is predominantly vacuum-lamp based, making it large and unwieldy. Sensors etc. would make the suit look like a walking junkyard, not to mention they'd be fragile. If you want to figure out subsystems for weapons, work within the ramifications of 1950s science fiction, not modern-day warfare.
A lot of what you wrote about additional subsystems (thermal imaging etc.) does not fit with the technology in Fallout. Fallout is retrofuturistic, inspired primarily by the way the 50s saw the future. The design of the technology is clunky, rugged, but reliable. Note the T-51b, the apex of power armour technology before the war. It is basically a plate steel helmet. Extra subsystems are limited to a polarized, bulletproof visor, a drop-down night vision eyepiece and NBC-sealed rebreather. This is because the technology is predominantly vacuum-lamp based, making it large and unwieldy. Sensors etc. would make the suit look like a walking junkyard, not to mention they'd be fragile. If you want to figure out subsystems for weapons, work within the ramifications of 1950s science fiction, not modern-day warfare.