What to buy Dear Days 2 on and DLC?

Simply put I have 2 questions. Number 1 is which is the best platform to buy this game on for longevity and the most players. No one around me really plays so I have no incentive to pick platform based on being able to play with them so assuming there’s no cross platform which system will have the most players?

My second question is what do we think the chances are of them adding more of the older vanguard cards (eg limit break and legion era) potentially as DLC packs?