Since the last Stark/BR16-patch i actually wouldn’t “keep trading up until you get BR-16” since the Stark actually feels better on Kira than the BR-16 does.(this is my personal opinion!)
And I would rank the other three options in this order:
-S81 because Stark + Drilled, it has a nice sidearm and mechanic can be useful to shave off a second or two when planting
-S41 the loadout I currently always rock on Kira,it’s loads of fun with the ideal weapon selection, add Quick Draw to that and you have a fantastic Kira loadout. i would have voted for it but I somehow prefer the S81 over it(grass is greener on the other side I guess…)
-S72 my least favorite loadout due to an unreliable side arm that doesn’t fit Kira IMO. Explodydendron is nice to kill people with the laser through walls(i.e. second stage of trainyard) but I don’t get much out of the other two augments