Took a look at the Blender 3.0.0 Alpha, hopefully to be released before the end of 2021. It contains the new Cycles-X render engine, pretty much a remake of Cycles from scratch using a more modern code base. The improvements it has are significant: Less render times per sample, more quality with fewer samples when denoising, and there's now even an option to set a time limit for your renders which will be extremely handy! Tiles are gone and have been turned into a separate feature to break up large images, trying to use them like before will now decrease performance... gonna miss the little orange squares but on the bright side we can see the full render as it's being sampled. All in all, this greatly increases the chances that I'll be doing more animations in Cycles rather than just Eevee, which needless to say would mean far greater quality.
This is a comparison from a new scene I made for (le sigh) yet another animation project with peckish vixens. In Blender 2.93.5, 64 samples will take 03:39 minutes to render... in Blender 3.0.0 Alpha, it's only 02:48 seconds for the same number of samples. The end result is also better, only configuration difference being that in 2.93.5 I use composite node denoising whereas in 3.0.0 I enable denoising in the render tab which is now the better option. I didn't use adapting sampling in either render for this test, but played with it in both versions and the new Blender Alpha offers much better results with it too!