`What's Coming Next: Rune engraving, which paves the way for a new deck editor ui, which then paves the way to card shops, and then maybe that gets expanded into a world map to explore.`
I say do all of that.
go full puzzle quest progression where exploring the map gradually reveals the complexity as something the player earned/discovered such as gating certain cards behind having faced against them already in the form of little enemy archetypes that unlock their cards when you beat them, and the multiplayer part as some kind of arena at the center of the world map with extreme emphasis as if it is the pinnacle goal of the map and primary source of progress completion but can still get there early before exploring everything else, maybe even immediately.
Having a scenario where a person can go fight 'weak enemies' to farm coins or roam into stronger regions to earn cards directly would be a catalyst for people learning the details of the game while doing something trivial or easy or mildly challenging or falling back on the low-stakes of PvE, which means it's probably worth 10x more than any kind of tutorial ever could be in terms of scaling out the learning curve. The simplest things could be common or lower level while the most complex ideas could be themed as bosses or higher level opponents, and then the complexity becomes framed as part of the difficulty. All along the way of exploring the player is presumably trying new things whenever they encounter friction, or studying what it is that is beating them without the pressure of a PvP environment, so the average player skill level would probably skyrocket even if the ceiling stayed roughly the same.
I'm sure you know most of this already, but it basically sums to saying that a world map concept has much higher value than someone might assume if they thought it's just a kind of novelty.