IMO the best mice ever are the Logitech MX Revolution and MX Master series that have an electronic clutch on the wheel. It's clicky by default but if you whip it the clutch unlocks and you can traverse an entire EULA in 0.6 seconds.

Some of their newer gaming mice have a half-ass version of this as well with a manual mechanical toggle.

I use a Elecom Huge with drag-scrolling enabled (check xinput if you're curious!). For any kind of scrolling I just hold a sidebutton down and roll the ball, it's very handy and feels better then using a wheel, even if imprecise.

For exact scrolling I'll use the scroll wheel or dive for the scrollbar.

What I really want is a toggle bound to a button for enabling/disabling drag scrolling. Most of my flow is keyboard based so being able to toggle that on/off for a dedicated stroller would be great.

I usually agree. However I got a Logitech MX Master 3. It has a magnetic scrollwheel instead of a mechanical one. That also enables it to have a little button to switch between clicky scrollwheel and free-spinning scrollwheel. Super handy!

Its battery lasts about a few weeks with above-average use (12+ hours per day, 7 days per week)