Yeah, the limited slots in N4 counterbalance things somewhat, but I would rather they had raised the base cost of an order in the formula rather than directly ("artificially" as people like to say) limiting to 1.5 groups. My off the cuff numbers are +5 points to literally every model in the game as a starting point, such that the top regular army size goes down from 30 fusiliers to 20 fusiliers. Combined with the rather steep price drops a lot of HI and TAGs got in N4, plus the fact that the order tax would hit more expensive models less hard than cheaper ones (50% premium on a 10 point fusilier, only a 10% premium on a 50 point model) would have probably resulted in a similar decrease in absolute order spam lists as the N4 cap did. Of course, nobody likes paying the same number of points for less stuff, but given the state of late N3, it needed to happen. And in the end, the N4 order cap still brings us there, but just gets there by a different route.
I think the ship where having Total Immune units be vulnerable to most/all non-lethal sailed when they made Flash Pulse have Stun ammo. Laving good ARO for ARO duty is one way to play. Leaving units you can afford to lose for ARO duty is another. If those are the same unit, then that's even better, but they don't have to be. Leaving rifles up for ARO is viable as long as you place them to maximize their advantage. If they were expensive, then sure, but they're not expensive units. They're cheap enough that finding something that's expensive or important enough to be worth a trade is typically always possible and sturdy enough that it's often not going to be a trade. Often I find that Rifle range is about where you want your opponent's bears to stall out. That's where they've spent the most orders and that's where you can spend the least orders digging them out. By the way, what is board advantage if a bear in the mid field doesn't count?