When I look at the big picture, the most important thing for me is that Bitcoin is immutable, and that it is the most secure store-of-value in the world, because there is nothing quite like it in that respect. I am willing to sacrifice things like scalability towards micro payments, because the one feature of Bitcoin is so heavily weighted in my mind. It's basically a billion-to-one ratio in terms of importance. Which means, yeah, Bitcoin's feature set may evolve extremely slowly in consideration to these other advances, but it's completely worth moving slow.
If there is a test network out there running an alternative version of Bitcoin that is experimenting with sidechains or drivechains and they show significant promise and adoption in terms of usability, with long-term proven security, I see no reason why we can't then start to discuss how those features can be merged into Bitcoin. Sometimes a fork comes up with a great idea, and there's no reason to block it once it's proven to be effective, safe, powerful, etc.
But until that's been demonstrated, I really am not a fan of changing anything other than bugs. It is a very personal take, and might push people to prefer to play in the grounds of altcoins, but my goal isn't Bitcoin being worth billions, the most popular, or Bitcoin being the best for daily transactions. My goal is Bitcoin being the ultimate store-of-value for the trillions upon trillions of fiat currency in existence. That alone will change the world in far more dramatic ways than people being able to buy coffee without a credit card.