I crawl from Debian 9.6 to Debian Sid. Here are my impressions. The system is stable, fast. Corrected some bugs in Terminator, when copying a large amount of files (from 20 gigs or more), the CPU does not load up to 50 percent (such was in the Stretch), on cold start up Libreoffice opens instantly (in Stretch it took about 10 seconds). The i3wm itself has become more responsive, many programs that I need, work smarter. Yes, I'm happy. Of course, I understand that it's rolling, you can step on the rake, but for the time being I'm happy.
P.S.
I did not use Xmonad because of the large number of Haskell libraries. And yes. Today Python upgraded to 3.7.1 version.
Screen locker