Too many to list, but wrt btc stuff, I'd really like to broaden the culture to one where well-intentioned people don't get canceled for heresy when they ask questions.
To take a hot-button example, the declining block subsidy, and what it will mean for btc security, is an existential issue. And yet people get buried in a shit avalanche if they bring it up, even well-respected core devs. It's hard to imagine a worse environment for threat modeling or for making a system resilient. Granted, the people who bitch and rant and threaten are overwhelmingly shitbags who contribute nothing to the ecosystem, but both science and history demonstrate that this kind of 'advocacy' is powerful even when the advocates are useless and contemptible.
I don't have a strong opinion on what the solution to dwindling block subsidy should be, or if a 'solution' is even necessary. I have a very strong opinion that being able to talk about it, and that having the dominant ethos of btc be one of serious intellectual engagement, is important. Being able to talk openly about things that matter, and not just parroting what the loudest Crypto Twitter thought-leaders say, is a big deal.
I'd like to change back to that.