I spent a couple months doing the 100+ per day, and I have to say I was underwhelmed with my results personally.
I don't get to practice much at all, but recently I've decided to slow my practice pace down, take fewer putts, but really focus on feeling the smooth transfer of momentum/energy from my feet -> up through my torso -> to the fingers -> and follow through. This has built my confidence for putts in that 25-30' tester range.
I've also begun to work on all kinds of stances from straddle to stagger, placing my back foot at different angles and depths (relative to my front foot) to mimic awkward lies, and to see how the rhythm for that aforementioned momentum shift changes based on foot placement.
I started doing that because I realized that my putting green confidence wasn't translating to on-course confidence if my feet weren't perfectly in the stance I practiced...so in other words I wasn't practicing for realistic scenarios.
TLDR slowing down, quality over quantity, helped me more.