If you are unsure on how server optimisation will help on the basis you have a lot of CPU and memory, that would most certainly emphasise why would need someone running your server. As while you can make a server perform better by increasing those if configuration is done correctly, you can actually make no difference at all by increasing these in any way if configuration is incorrect.
Just as a very very basic example. If your mysql is set to utilise 8gb of memory, you can add 500gb to your server, and it will make no difference unless you change the way mysql is configured accordingly.
In terms of cloud, we have US and EU based servers. We also have many customers using cloud in the middle east