What I am going to suggest is some things that you can change in survival if you are looking to change some rules. These will be ports from custom but will be limited.
Here are the ones I think should be in vanilla
-Max blockhead settings (minimum is 1-3 and Max is 5)
-Trade portal settings (Free is disabled and not there) (jobs are togglable)
-Seeds (Time crystals will be affected with this setting. And will not spawn in same locations but will make it so you can have the same map )
-Portal chest settings (enable/disable)
-Gem pickaxe and gold bed settings (would be in custom and survival) (can be enabled/disabled)
-ownership sign settings (expand enabled/disabled) (sign disabled/enabled) (both custom and survival)