Don't romanticize that 5D Classic too much. 😜I bought one recently and headed out this morning for the second time to find the OVF looked like I was looking through a periscope. I guess there are disadvantages to having a 12lb mirror slapping around in there as the focusing screen was trying to escape. Don't take the advantages of mirrorless for granted folks!
And as you mentioned the M240, you know when I was most satisfied with its default colors? The last test shots in a parking lot as I was showing it was working properly to its new buyer. I took some of my favorite early pandemic shots with it, all monochrome, but was preoccupied with digital medium format at the time. 🤦♂️
That sale led to the SL though, whose default colors I loved immediately. It has a look, that was unfortunately eliminated in the SL2 (the SL2-S is rumored to be in between, but I have my doubts). I'm sure it could be integrated into other systems more easily and better edited from a more neutral starting point, but it does seem that something special was eliminated. I certainly can understand if you also struggle with it. A lot of complaints online. Still there are options (I'm looking into Cobalt) and besides the IBIS and video functionality you mentioned, the Monochrome High Contrast profile and highlight weighted metering are pluses of the recent Leicas including the SL2.
EDIT: Anyway fixed the 5DC before a little art & wine fest this weekend...