I think the superior range of the HMG makes it well worth the SWC 2 and frankly the MK12 is not worth its extra points costs. As Kiwi Steve points out, a burst 3 heavy pistol is plenty for short range. Why are you taking a multi-rifle on a Kriza? Madness.
I'll bet people will end up with lists that use the other two Krizas because it works out with them. But they don't fulfill a basic need like the HMG does so it's not going to be the main one.
I find it much easier to justify the swc of HMG over the extra points of Mk12 too. I have started many lists with the Mk12 and ended up swapping him for the HMG just to make things work.
Honestly, I think the Kriza HMG would be better balanced with a 360 visor. The extra cost would push it out of reach of a lot of lists but with a degree of additional utility that would have made it not a pure tax.
I think the Multi-rifle variant is underrated. AP rifle roundscan end up doing more damage than HMG or mk 12 rounds. also, in missions where scenery can be destroyed, the rifle can do the job.
I see a problem here. AP ammo on rifle (damage 13) performs better than damage 15 weapons only when the target's armor is 6+, so if your meta isn't TAG-heavy (and, well, even if it is - TAGs are kinda the most un-spammable thing in the game), it isn't going to matter often. I'd even say Shock ammo on MultiRifle is more interesting than AP, since in my meta there are a lot of Dogged/NWI units for it to kill. But, well, Mk12 profile offers some of this MultiRifle functionality in form of SMG - it, too, can shoot AP/Shock. At the cost of having worse rangebands on this ammo types, yes - but that is offset by having better rangebands overall. The second part about destroying scenery is kinda valid... but in my experience, destroying stuff generally was not worth the orders spent. And rifle, again, has lower damage than things I usually use for demolition (Feuerbach, MSR, ML, DA-armed melee dudes).
I feel like you have to include the sub machine gun though. You are definitely paying premium for having that over just a pistol.
Not sure why the MR gets so much hate. I mean, from my POV only the HMG profile exists and the rest are just "dead" profiles to me. But if we lived in a world with only the MR or the Mk12 to choose from, I'd choose the MR any day of the week. 13 points more than the MR loadout is just garbage in my book and atleast you can do niche things with him, like burst 2 Stun Mode in Hunting Party and stuff. Also I face waaay to much Broken-Islam and posthumans to care about a poor mans HMG over a weapon loadout with Shock. YMMV.
Not entirely sure if the platform would affect the cost that much, either way even if it doubled the price to a whopping 4 points it would make a MK12 10 points, which is way too much in my opinion
If they gave either the MR or MK 12 profile Specialist Operative it would see more use, could even see the fabled 2 Kriza+Hollowmen Haris. I also think the Missle Launcher would have been a cool choice too.