So here's what I LIKE as a meta progression:
- Complexity: you start with the most straightforward options and later unlock more complex tools. In Against the Storm, for instance, you start the game with buildings that have one, two inputs at most and later on you unlock more complex production chains. In Diceomancer (another game with gr8 progression) you start with the most basic class and later unlock more complex play styles.
- Story reasoning: in StS there's an in-game justification for the meta progression, same with Tainted Grail: Conquest. Very, VERY few indie games do this, but it's nice when it happens.
- Alternative tools: in some games you unlock alternative loadouts or skills via some meta currency. For example, in Mechabellum every unit has 3 technologies that are selected before the game starts. Meta currency is used for purchasing alternative techs, though for most units the basic loadout is either optimal or "good enough". In FTL you unlock new ships and in most roguelikes you can unlock a character or class after a bit of grinding. If the grind isn't too terrible then I think it's fine, sure, add a sense of progression to the game. Whatever.
- Ascension: a bit of a different topic, but almost all roguelites have an ascension mechanic, meaning difficulty levels that stack penalties atop each other. While I like more challenge for the hardcore player, I must point out that ascensions ALWAYS make you go from "huh, such a fun little indie gem" to "**** THIS ****, RNG ****** ME IN THE *** AGAIN!!!" very quickly. More importantly, in every high ascension the pool of viable strategies tends to shrink and the player ends up forced to play one of the few "meta" strategies. It was a nice sense of achievement to beat ASC 10 on Trials of Fire, but realizing some of the really FUN characters are simply unplayable at that level left a bad taste in my mouth. In a perfect world all viable strategies would scale equally.
- POWER: if I open a meta tree and see "+X% damage/health" then you can bet your *** I'm going to cheat. If I can't cheat the tree then I'm refunding the game. There is ZERO justifiable reason for making the player more powerful in between runs. Zero. If you think otherwise then you're ******* ********. It should also be noted that many games offer things like RNG-mitigation ("the first reroll is free"), run start bonuses etc. All these perks fall in the "power" category and shouldn't be included in the game.
- Essential options: Sometimes the game will try to convince you the meta unlock is just an "alternative", but it clearly isn't. In TKiW for instance you have a ton of advisors and advisor slots. While the advisors themselves could be classified under "alternative", that's simply not true since the game itself knows some advisors are better, being more expensive, harder to reach or both. Other games lock BASIC functions behind a ****** progression.
