It seems like it would be cheaper in every single way worth measuring to simply build another Stormcrow line than to design, build, and propagate an entire new Heavy Omni though
Since this is the Clans, there's always the question of did the Wolves have the plans and own the production rights to make a new Stormcrow factory?
Also, while the differences may seem a lot at first (17.5 tons of pod space for the Linebacker vs 23 for the Stormcrow), it's not quite so much when you account for the Linebacker's 4 extra DHS fixed to the chassis and 1/2 a ton more Ferro. In a way, the Wolves did build a Stormcrow factory, they just fiddled with some of the base settings like total tonnage and crit placement (2 less in each arm, 2 more in each side torso).