I feel like the base armor core should be a free reward just like the yoroi set, or alternatively be made available for all to use once the original release season has ended. (I do not mean any of the further armor pieces gained from owning the battle pass, only the core itself)
This would allow players to still have access to a different suit on which to earn rewards from the weekly challenges or events and also open up the possibility of having store bundles for the core, neither of which seem currently feasible with the Reach armor core as it is only for pass holders.