Hello! I work on the combat team, and can hopefully answer this, or at least shine some lights on it.
When we (as in the combat team) set up weapons we usually go by the models of them. Bigger or heavier looking ranged weapons tend to get tweaked towards the low RoF/high damage spectrum, while smaller and ligher looking ones go the other way.
That there’s been a pattern of blue-ish weapons being fast and light while orange-ish ones being slow and heavy (and the green-ish being a middle ground) is actually a pure coincidence from the balancing point of view.
For the damage (and fire rate and therefore total damage output), it will of course depend on how the stats are rolled, so I’m going to base this on all stats being set to 50%. And with that baseline the Mk VId will deal less damage per shot than the Mk II.
But when including other things like the firerate being about 50% faster, similar spread as the Mk II while aiming, and being more mobile in general, the Mk VId might very well be overshadowing the Mk II by too much.
In short, I’ll poke a designer on my team about this for potential tweakage of damage or other settings, as I’m just a lowly programmer.
All three Accatran Recon lasguns should be available for both the Sharpshooter and Psykinetic, so if you only have one of the marks available for either of those (when fully levelled up) I’d recommend you to log it as a separate bug.