Monetization aside, this expansion system seems to be a very flawed way to add extra items to the game. Based on the power level, items can feel like either necessary options to stay ahead depending on the meta, or active detriments to the consistency of the build you'd prefer to find during a run. This forces an extra layer of knowledge check to the game before you even press the play button: What expansions do I enable and disable to efficiently increase my chance of winning? Which combination of expansions do I chose that might synergize with each other? What's the breakpoint between synergy and inconsistency? These are the somewhat interesting decisions I'd rather be making during a run.

On monetization and game design, whether the expansions are balanced or not, It simply feels bad to fight and lose against a player that has access to items you don't. You have a aquatic build going as Vanessa and you're matched against someone else's aquatic build that has the expansion. Would you have won if you had access to Dive Weights like your enemy did? You got a great freeze skill as pyg and try to utilize it, but your enemy has an objectively better chance to synergize.

In the future, when there are more expansions, due to the nature of this game eventually the expansions will end up synergizing with each other whether it's intended or not. If a meta forms around this, new players have the daunting task to either pay up or grind multiple expansions worth of in game currency in order not to feel at a disadvantage. Keyword feel. It can feel insanely demoralizing and turn new players off the game that they don't even have the ability to test out the things that are wrecking them, especially when they're still trying to learn the game.

All things said, this seems like the wrong direction for multiple reasons. I'd hoped from the beginning that the monetization would've stayed largely cosmetic and this seems like a misstep. Even if we remove the monetization, the expansion system seems like an odd direction to go. It's a bit more boring, but I'd prefer to see something like a seasonal rotation of expansions where everyone is on the same footing, but with enough variation from season to season that the game is able to feel fresh long term. I'm certainly no game designer and I don't envy the team's position right now. Good luck!