Sound slide you want the calls right, as long as it's fast, and if that can't happen, then challenges shouldn't really be a thing.
I'm kind of in the same boat. I don't think managers should be responsible for questioning whether the call is right or not. Use tech to get the calls right in the first place. But until then, the challenge system is the best they have so make it faster.
I agree with other suggestions that there should be no consultation with a teams own video review, you either challenge in real time or don't based on what you, your players or your on field coaches see, and you get 10 seconds to throw that flag.
Pitch clock for pitchers is absolutely essential too imo.