Depends how you define "casual" - coal is the easiest resource to get and (most likely) you don't have the time limit to farm it. While other "Legendary commanders" were available in the armory, they were never purchaseable with coal - only for the ongoing update special resource, which you had to grind in a limited timeframe. Kuznetsov was obtainable with 10 skill points during the "Victory" event too.
ELO does not really support team-based games well. XP mostly rewards damage, kills, capture and defense. It can be improved on WG side but it will never be able to accurately "judge" player actions on battle outcome. What I would like to see is a ranked season with zero-sum system (no save--a-star). If we can't get that then at least try moving the additional star to the top player on winning team? For one season just as a test.