>>112208680SU was planned from the very start
Loud house was out of nowhere but they didn't shove it down your throat, and it wasn't put at the end of the series
Korra was added at the last second to try and regenerate interest in the series way after people either stopped watching it or called it shit
Adventure Time had to literally rewrite their personalities, ignore early characterization of bubblegum entirely, and felt extremely tacked on
Star vs. was basically one writer inserting their viewpoint into that character and both came out of nowhere and wasn't even consequential or explored, and didn't even have hints of buildup like AT did or you could even argue Korra did in a few scenes
SU > LH >>>>>>>> Korra > AT > Star