Should be noted that Stormtroopers do start with a passive cloak and part of their cost is to infiltrate them in. While the Bundle is now on cooldown, they can still do sneak attacks with it later on.
I'm not sure on giving them Ober rifles because while it's a kar98k, it's a very very good kar98k in terms of accuracy and damage output.
Hence the suggestion. It deals the exact same damage, it just is very accurate. Storms would consistently be able to deal damage at all ranges, but being 4 man squads without LMGs that have to upgrade for StGs, an accurate rifle might be exactly what's appropriate for the unit. I mean, it's not like unupgraded Obers are a concern.
It'd also justify their cost as well. Hell they could cost the same as Panzergrens.