The Ratnik Molotok is I think the way to go. Despite his heavy armor, the Ratnik really needs Suppression fire to live, and unfortunately the HRL profile has no such weapons (not even an SMG!) capable of suppression. Also he is the only solo piece in Ariadna to get 5 burst (dual molotoks), so can somewhat go crit-fishing, though I wouldn't rely on it. 54 points and 2 SWC is expensive and he's never a piece that is really going to "make back his points". His value more comes from the fact that he's a very different type of roadblock to the typical ariadna camo diversions people are used it. In terms of how he plays in the Vanilla Ariadna/TAK ecosystem - he makes a great Datatracker and his multiple wounds/high Armor are an exceptional contrast to the sea of 1-wound, no armor camo tokens that surround him.