In my humble opinion and I am still a beginner and I rarely do outbound.
try to be short, simple and specific. Don't use templates or generic words trying to sell.
Maybe you don't even need to try to convince much. using words like clicks and google traffic profit may raise flag of a spammy type of email, you know the one that we all see and delete.
here is an example of an email I just sent for the owner of rubyguides . c o m a website to teach the ruby programming language: (text in green is my notes for you)
Hi {insert person name} very important to include the real name if you can get it, it makes more personal and specific
Hope you are doing well.
I have learnt Ruby by myself like 5 years ago. I have also stumbled on your website and have a subscribed a few months ago. try to connect yourself somehow to the domain name/the business / the person behind them
But I rarely use Ruby these days. this may hint reason for selling
I am checking if you would be interested to acquire the domain name r u b y. g u i d e from me for the price of $100. Yes fixed low price, am saving his time, and did not talk about how good the domain is, he probably know. the more you advertise the more annoyed the receiver is, and feel cheated.. he is already not happy receiving an email, believe me.
Its renewal price is about $25 per year depending on the registrar you use.
Thanks