Chess is about an even battle between 2 players who each have hundreds of possible moves at any point during the game. What makes it interesting is the huge number of possible moves our inability to analyze them all.
Mario is about having good timing and reflexes. Players find it fun because they see their skill level go up as they progress in the game and need precise timing of their jumps.
The thing with RPGs and character progression is they usually come together. RPGs are usually simple. You have some choices, but it boils down to 1~3 obvious choices. This gets boring after a while because the outcome is determined by the stats and RNG, not the player's ability to analyze complex situations or the player's ability to time button presses. To compensate, the player is given rewards in the form of items and level ups. Take any roguelike and remove loot and levels. This would be a very boring game.
If your game has the complexity of chess, then you could do without any form of character progression. You provided complex turn examples, but that doesn't mean the game has the complexity of chess. When the player understands the game mechanics, if he's left with an obvious action chain, it becomes as simple as a roguelike where all you do is mash the direction key until that "k" disappears, but with extra tedium thrown in. If there are still lots of interesting things you can do at that point, the game should stay fresh. This could be by having a bunch of flow changing abilities, using the environment during combat or something else that prevents having an optimal action chain at any point.
Thank you very much. It may simply be how I needed it explained, but either way this helped me quite a bit.
I'm pretty confident that my game at it's current stage would barely compete with the intricacies of tic-tac-toe, let alone chess. I'm constantly trying to add to it's complexity while also keeping it very simple to understand/use.
The examples of flow changing abilities and environment are exactly what I was looking for. I'll more than likely start trying to consider the environment as my next big challenge once more bugs get squished. Thanks for the pointers.
If anyone else has any good ideas on how to expand on this, please feel free to let me know

Find content
Not Telling