I've just reached Gateway Bravo in The Surge 2, so I'm a decent ways into the game. Most of my gear is now at Mk. V or better, except for my implants. Those are still on Mk. II, since I have only found a single Mk. III Implant Circuity component thus far. Is this intended, and I'll be finding more later? It's a tad frustrating to only be able to stack 3 healing injections this far into the game.
I seem to have progressed far enough into the game where Implant Circuitry Mk. IV is dropping. It's possible my game is bugged, but the Deck13 support site doesn't currently list this as a bug. An improvement of the sequel over the original Surge is that higher marks of components can be downgraded to a mark lower, so my Mk. IV circuitry was able to craft the Mk. III heal injection, and also upgrade to Mk. IV.