1; Give ober double shreck? Sounds like an awful idea to me. This would completely go against the units intended role: Anti- infantry firepower. Not to mention i wouldn't like the idea of having 2 expensive Ober squads just to have proper AI and AT, when compared to the allies. The Sturmpioneers, despite being overburdened, would be way more fitting for the AT role, which is slightly reinforced by several voicelines that they have when they have a AT weapon: ''Aim for the armor's weak points!'' among others.
2; Early raketenwerfer certainly is not enough for the lategame. putting the raketen's current performance aside, there are plenty of late- game tanks that can serve the AT role. This however requires planning ahead of time in order to decide what tank is best suited for the current timeframe and map control. Having the ability to just completely ignore that and get Obers for your AT roles with 2 panzershrecks would give a decent chance of it becoming the new, boring meta.
3; Everyone uses Jagdtigers for heavy's. dunno what you mean with this, really.
1. If not obers, then create a new panzerjaeger infantry unit with the same model, like the panzer busche squad from COH1, except with 2 schrecks instead of only 1 (schrecks were good back then), just make them a bit cheaper than obers.
2.Right now the late game hard counters to Allies tanks that OKW have are jagdpanzers and panthers. Jagdpanzers are just decent, they were good before, now just decent because they are like 10 times slower than the stugs that they try so hard to imitate, not to mention they often get rushed by medium tank blobs because you know, OKW can't lay down a lot of defensive AT fire compared to Ost with their panzergrenadiers. Let's also bring up the price of the jagdpanzer, it is certainly overpriced for what it does, I'd rather have a cheap, easily replaced stug with its blistering RoF all day. OKW panther is nerfed so I don't use it anymore, even with the reduction in fuel cost. Why? Because the massive buff to the jackson, fielding offensive TDs to chase it down is pointless as it now has a fat HP pool, like it recently ate a lot of fries and burgers but somehow kept the punch it always has. It's not rare to see jacksons rolling with meds late game.
3. What's the point of using the Jagdtiger after the changes to tanks anyway? It doesn't 2-shot those mediums anymore, in fact, it is the one that gets steamrolled by hordes of meds, just like the jagdpanzer I mentioned above.
I mainly speak the truth that is present in team games nowadays, in smaller game modes those issues are less annoying.