These are strictly ideas. Not sure how well it would play out but it would spice up gameplay.
Base suit- Nice all rounder, no special abilities
Combat suit- 50 extra body hp, smaller window for critical component repair, 25% slower on foot speed
Engineer- 25 extra shield hp, 25 less body hp, larger window for critical component repair, extra carry slot
Hazmat- 50% fire and radiation damage resistance, 25 lower body hp, 25% faster on foot speed