Quoted By:
I would say at least keep the best aesthetic features with every new iteration. Customization should definitely be kept, but seasons aren't necessary. Soaring I can see as being a fun Hoenn exclusive feature due to Latios and Latias being native to the region. Although I believe that following Pokemon help to give a unique, memorable adventure as well.
I would say keep:
-Day/Night cycle
-Difficulty Modes
-Customization
-Following Pokemon
-Super Training
-PSS
-Friend Safari
Have only one of:
-Contests
-Musicals (I guess)
-Something New
Have only one of:
-Battle Fronteir of any kind
-Battle Institute
-PWT
-Pokethlon
-Something New
Dont bother putting into every game:
-Seasons
-Soaring
-Game Corner
-Amie
-Roller Skates
-Riding Pokemon
-Cafes