I dropped from 26t to 24t on my LHT. I would have gone to 22t if my equipment allowed it for a reasonable cost. I found a significant difference between the two. The 8% drop in my lowest gear was quite noticable on really steep grades, on which I often (always?) ride slower than 3.6 MPH. The lower grade allows a noticably higher cadence up these steep grades, reducing stress on my knees. My ride has 26" wheels, so I estimate my lowest gear at 18.4 gear inches now. This is about as low as I can handle with my current bike-handling skills. I need to keep enough speed to steer while spinning up those hills. I've read on this forum that other more skilled riders have gone lower with good success as well.

Front shifting is not as crisp, between small and middle chainrings. I only make this shift in bail-out mode anyway.

I find that it's much easier to spin up hills at walking speed than to actually walk.

That's been my experience. I am not a performance-oriented cyclist, so your experience may differ.

Jim