base2 

For unladen smooth road use. I found that with the riding I did, I mostly stayed in the 44 & I was mostly in cog 10 through about 5 or 6 on the small end of the cassette. Position 11, the 11 tooth wasn't used very often but it was very nice to have. I didn't really use the 28 all that much.

Now for fully loaded panniers or gravel riding the situation was well reversed. The availability of the 28,40 combination was nearly ideal. The whole cassette was used for the duration.

I have found that for non-paved surfaces anything lower than about 15 gear inches, it's hard to pedal fast enough to stay upright. The balance between traction, strength & speed becomes unworkable for me.

So, 19-ish gear inches afforded by the 28 tooth ring (for me) is about the bottom of the useable range anyway. Enough purchase per pedal stroke to maintain balance, a low enough cadence to stand & jockey weight around for traction, & enough strength to keep the whole situation moving forward. In short, anything steeper/looser & I'd be walking anyway.

FWIW: A 0.7:1 drive ratio is wicked low. If you have individual cogs like with Shimano 11 speed cassettes, the torque can bite aluminum freehub bodies pretty hard. It would be best to stick with steel or titanium in that case. Otherwise, pinned/riveted cassettes or monoblock designs like XD start becoming good ideas.