Each pack has about 5 themed tracks, each about 2min long. So I would say worth it for prototype or small game but not really enough content for a full game.
I have only killed plants in self watering pots (with soil). Semi hydroponic is the way in these pots as far as I’m concerned. Pothos worked pretty good for me.
Of course! ECS is Entity Component System. In short: separat your code into logic (=systems) and data (=components) attached to game objects (=entities). It enables you to add different behaviors to your game objects by composing different components together. An example: I have a system called RenderSpriteSystem which automatically renders every entity that has a PositionComponent and SpriteComponent attached.