Is overclocking easy ? Not too difficult.
But, as you've pointed out, it will work it harder and heat dissipation becomes marginal, you will probably need to upgrade the heat exchanger and fan unit.
Is it worth doing ? That'll depend a lot on what you intend to do with the PC. Generally speaking gamers who want to squeeze the last possible ounce of performance from the CPU will say yes, nearly everybody else will say no. When your main point for making the change is to save power then overclocking would appear to be entirely counter-productive.
You may like to read this click here has a few hints on how to optimise power savings in the BIOS.