Joomla Performance Optimization Expert

Note that I am NOT looking for SEO/Link Building or any content optimization. I'm looking for a Joomla performance optimization expert who is experienced in making huge websites run faster. I expect the following to be done: - better SQL queries - more efficient source codes - tune MySQL configuration optimization - convert "tables" to tableless "css" - unpublish features that are not used - install accelerators on server I do not want any changes made to the structure of the database. Please show me a list of the past Joomla optimization projects you have done and please give the performance improvement benchmarks.