I enjoyed reading your review! I found it interesting as I'm ever deciding on my lenses and have yet to find "MY" setup with Leica (I'm losing track of how many lenses I've bought and sold since switching to Leica in 2014).
I have one digital body and one film body and I'm trying to decide right now if I want to commit to one lens for both bodies and thinking of the 35 Summilux FLE. The catch is that though I do like 35mm and have used it often in the 20 years I've been shooting as a pair I definitely prefer 28 and 50mm which is what I'm using now (28 Elmarit Asph and 50 Summarit 2.4)
The catch of course is that I don't really care for the 28mm framelines on my M240 or my M-A (though certainly usable) and to me the 50mm frames are just a bit smaller than I'd like. Ironically, to my eye, the 35mm framelines are perfect for how I like to shoot with a rangefinder.
*sigh* Endless decisions. One day I'll figure it out!