Essentially, there is an economy of experiences had by the player over the course of the players life with the game, and if you have long-sessions and want long-term engagement this economy needs just a much care as the economy within a single session does.

When introducing new terms/strategies to your cards, if you're looking to bring in causal players it can be helpful to have a gameplay reason for them to engage with the new mechanic heavily. For example, you could give them a mill-deck to try out if that was a strategy in your game.

When I play a new deck-builder I've found the best tutorials are a bare-bones first match that's on rails. Then I like to have the tooltips on key terms in case I forget or need clarification on a new term. I'd prefer only the tooltip for a specific term to be shown on hovering that term/section.

This is an interesting thought. How would you define desire vs. motivation when it comes to game design? To me they are very close terms, desire is the feeling of wanting something while motivation is the factor in the game or in the player which creates that desire.