It seems like some of these (perhaps all of them other than fixing the "+1" problem) can be done via API clients instead of via GitHub itself implementing it. A third-party website can do wiki searches. A separate service can send you email notifications, and you can turn off built-in emails. Even the +1 thing might be solvable with a bot that edits each bug report to add a clickable +1 badge (a la the CI build-passi…
>This is GitHub after all; why don't we build stuff ourselves instead of waiting for a centralized closed-source company to decide they care about our features? Why would I build something for a centralized closed-source company?
If you don't build it and you wait for the centralized closed-source company to, then you're putting your project even more in their hands.