He doesn't need to go to all the trouble of going to all those areas and doing all you said, CCleaner does all that and more and takes about 30 seconds to a minute to dump Temp Files, History cookies and more it even dumps your recycle bin. If you use the CCleaner then do the optimization or Defragmentation which takes just minutes you'll have your computer working faster in a matter of a few minutes.
Relying on any third party to maintain your computer is akin to dropping you mower off for repair, picking back up again and never asking the mechanic what was wrong & why it happened.
While there is nothing instringically wrong with applications like CC Cleaner, any thing that is used large scale becomes a target for criminals, ego maniacks & manipulation by the application owners themselves.
Which is why Microsloth products ar the most often hacked, because there are more of them out there and macs get fewer because they are a smaller target.
Remember when the largest virus protection company a the time, Norton ( I think it was ) was found guilty of distributing mal wear in order to boost the sales of their "fixes" thus Semantic got Norton for a song.
Applications like CC Cleaner fixing your computer is like changing your bent blades but not removing to rocks you continually run over which bend the blades.
Doing all that I posted, not only replaces the bent blades but removes the rocks from the lawn itself preventing further blade bending, till more rocks are uncovered.
All commercial computer fixing softwear do almost nothing to prevent future infections other than to send you a warning that you need to spend more to all the time to be safe, when with a few simple procedures you can set yourself up substantially more securely with out relying on something you don't understand or know about magically doing a job on your computer.