If nods to the Souls games and Team Ninja’s Nioh aren’t enough, perhaps we can interest you in an idea borrowed from
Nier: Automata? The medbay in the ops centre allows you to upgrade your rig’s core capacity using implants. You’ll star with four slots, to be filled with various bits of kit such as devices that allow you to heal while out in the field, see enemy health, or increase your HP pool. Every implant drains power, however, so you’ll also need to manage consumption. Raising the maximum capacity will open new implant slots (up to eight in our build) which should allow plenty of scope for customising the game around your playstyle.