www.novelupdates.com
Read the synopsis. As of chapter 25 the MC has below average talent even compared to the other mob characters and only cultivated to the second realm because of pills. It's actually been more focused on literal cultivation(agriculture), but seems to be shifting focus on a plot point I won't spoil.
You can also try "Record of a Mortal's Journey to Immortality", haven't read past the doctor part but I've been told his breakthroughs were pretty slow paced compared to other popular Xianxias.
SELF-PROMOTION INCOMING!
Also I wrote one chapter as a proof of concept for a story with an MC with an abysmally low cultivation speed and relatively low strength compared to her peers, like, to the point she's about to die and still in the first major realm.Though uh, it's gonna involve manipulation of teenagers and their probable deaths as she gets more desperate to extend her lifespan. Pretty dark so wouldn't really compare it to CCG, probably won't even be motivated enough to continue writing it.