Common configuration file

Sorry . Here i have 2 queries. first query is related to performance improvements and another query is related to standard configuration settings

For performance Improvements:
Right now i am hiding unwanted columns using privateattributes and i am keeping model in cache (as middle ware). do we have any other tips for performance improvements ?

Regarding configuration Settings:
I am asking about Standard (best practices) configuration Settings for server ,database, security,response,request.
For example , In Server configuration file, we will have host and port information (by default option). do we need to have any other settings ?

Is it clear now ? sorry!

Thanks!