njkayaker

https://www.bikeradar.com/advice/buy...-need-to-know/
(Posted earlier; easy to find.)

Shimano improves each line across generations. For example, the current 105 line is better than old/ancient lines. Shimano also moves features to lower lines (so the current Tiaga might be better than old 105).

105 is the "bottom" of the "better" lines. Outside of number of gears (and electronic shifting), there's there's not much of a benefit to picking a line higher than 105.

If you don't like how the lever works, it seems like you shouldn't be much interested in it. It might have been done that way to save some manufacturing costs.