Looking for performance tips for a high-traffic, high-profile site?

Looking for performance tips for a high-traffic, high-profile site?

1. Checkout the number of plugins you are using
2. Ask someone or if you are a developer yourself so must review the codes of every plugin and your theme for useless DB calls
3. Don’t use cache plugin or any plugin which is not necessarily required because every plugin means an extra load for every single page/post visit
4. Hire someone for apply conditions on your theme, plugins and other JS/Ajax scripts to reduce number of requests which ultimately open DB connection or use bandwidth uselessly
5. Hire someone who can assure you that he will cache your website (Without any ready made plugin, but manually)
   e.g.
   Script Files: for 1 month
   Images: for 6 months
   etc.

   Notes: An expert will easily understand that what am i asking to do him.

6. If your website loading time is already really good except home page? So you may ask someone to review home page specifically.

I hope this will help.